Tag Archives: BIBS insulation

Post Frame Condensation and Insulation Challenge

Solving Yet Another Post Frame Condensation and Insulation Challenge

Long time loyal readers will sigh as yet another post frame building has been erected without thoughts to how to properly insulate and control condensation. Had our new friend invested in a Hansen Pole Building, chances are good we would not be having this question and I would have had to write about something else today! Our Building Designers follow with these recommendations: https://www.hansenpolebuildings.com/2019/11/post-frame-building-insulation/.

Our new friend COREY in POST FALLS writes: 

“I have a 36×48 pole building with trusses on 12’ with BCDL 5psf, the roof is plywood sheeted with composition roofing with ridge vent and gable vents. The wall Purlins are on the exterior of the poles and there is no vapor barrier. I would like to install a ceiling with insulation and insulate the walls. I am looking for vapor barrier and insulation recommendations. Was thinking of installing 2×4 on 24 centers to bottom of trusses and installing OSB and blown in insulation, and then framing in between poles adding batt insulation and sheeting with OSB, but am unsure of controlling vapor. Thank you.”

Mike the Pole Barn Guru responds:

Small world, many years ago I graduated from Post Falls High School!

A vented ridge relying upon gable vents as an air intake is usually very inefficient. You should make sure your vents in each end are located in the top half of your attic and have at least 415 square inches of net free ventilating area on each end. This means you are probably going to have to add more vents. Effective ventilation of this area is essential to preventing mold and mildew in your attic.

Wall girts flat on column exteriors are inadequate to carry imposed loads and will not meet deflection limitations. I would suggest you reinforce each of them to create either an “L” or a “T”. Assuming you have 6×6 wall columns, you could place a 2×8 bookshelf style girt on top or bottom of each girt, nailing through 2×8 into existing girts with a 10d common nail at say 12 inches on center. This will create an insulation cavity and allow for easy interior finish.

For ceiling joists between your trusses, 2×4 will not be adequate you should use 2×6 #2 with joist hangers on each end.

Unless you have a Weather Resistant Barrier (https://www.hansenpolebuildings.com/2016/01/determining-the-most-effective-building-weather-resistant-barrier-part-1/) between framing and wall steel, my recommendation would be to have two inches of closed cell insulation spray foam to the inside of wall steel. Then fill balance of wall cavity with BIBs insulation: https://www.hansenpolebuildings.com/2011/11/bibs/ with a well sealed vapor barrier towards the inside space.

Participating in Rick’s Post Frame Cabin Planning

Participating in Rick’s Post Frame Cabin Planning

Happy readers have been following Hansen Pole Buildings’ Designer Rick’s journey towards constructing a new cabin. Rick has graciously asked me to jump in with sage advice (yep, Rick and I are both old guys), as well as answering some questions he has posed.

Rick mentions using a vapor barrier under his thin concrete slab. This should be a minimum 10 mil with 15 mil being even better in resistance to possible tears prior to floor being poured.  (https://www.hansenpolebuildings.com/2017/11/vapor-barriers-slabs-grades/)

I’d believe Rick’s cabin floor could be insulated with closed cell spray foam two inches thick, providing approximately R-14. Any wiring or plumbing extending through sub-flooring could be routed directly vertical through foam and this should not pose a challenge of access for any future system modifications.

As only incidental heat will be provided into crawl space areas, using rigid foam insulation boards beneath a thin concrete slab might very well prove to be an undue expense.

Rick’s sub-slab insulation boards (if used) and approximately two inches of concrete will not pose any design issues when used with a 2×8 pressure preservative treated splash plank. With top of floor OSB three feet above grade, a clear height in crawl space of two feet will exist under the floor joists. A row of stub columns at building center will carry beams designed to support joists. Given relatively small floor joist and beam spans, there would be 20 inches or more between concrete and the bottom of beams.

A consideration for wall insulation might be to use a flash coating of two inches of closed cell foam against siding, then fill remainder of wall cavity with BIBs. This would eliminate a need for a Weather Resistant Barrier beneath siding and would provide as much as R-35 insulating value. If looking to super insulate and eliminate any thermal bridging, two inches of insulation board could be glued to inside of framing, further increasing R value.

So far, I am liking Rick’s plan of attack and look forward to reading more along his path to his best possible design solution.

Pole Barn Cabin Part II

Today’s blog is a continuation from yesterday….Rick Carr, Senior Building Designer for Hansen Buildings shares his thoughts on planning his new pole barn cabin.

From JA Hansen, co-owner of Hansen Buildings….Thanks Rick!

Next I dealt with the crawl space:

After deciding that I want to do a crawl space, several design issues arise and decisions on how you will deal with those issues can affect how the building is designed and ordered.  All reading on crawl spaces emphasize making sure that you avoid moisture issues in the crawl space.  Next you need to do something to avoid losing heat to the ground and out the sides of the crawl space, this crawl space being above grade.   How tall do you make the crawl space?  Do you “condition” the crawl space?  How do you insulate it if you do “condition” the space?  Most crawl spaces are underground with a foundation wall, but that is not the case with post frame buildings so there is very little information out there on how to plan the post frame crawl space  and to “do it right”.  I have read the five blogs articles on crawl spaces, but there are still unanswered issues.

https://www.hansenpolebuildings.com/2013/03/crawl-space/

https://www.hansenpolebuildings.com/2016/04/foundation-and-crawl-spaces/

https://www.hansenpolebuildings.com/2018/06/conditioned-post-frame-crawl-space/

https://www.hansenpolebuildings.com/2018/02/insulating-post-frame-home-crawl-space/

https://www.hansenpolebuildings.com/2016/12/cost-savings-crawlspace-vs-slab/

I will present what I think that I want to do and I’d like to get Mike the Pole Barn Guru’s ideas on it with a question or two.

I plan to condition the space, so I would put down between 6 and 10 mil plastic, then 2 inches of foam board insulation followed by pouring a concrete floor, just enough to keep critters out.  I plan to use BIBS insulation in the walls, so I would extend that down the exterior crawlspace walls to the concrete.

 

The radiant floor heating people that I am talking to have recommended that I put between R-13 and R-15 insulation on the underside of the sub-floor.  The reasoning is that heat wants to move to cold and that you don’t need the crawl space heated to the same temperature as the living space; so insulating the underside of the floor keeps most of the heat up in the living space.  I need to talk to the insulation contractor about what type of insulation to use here.  Spray foam might be good, but the spray foam would make working on any plumbing or electric that is run below the floor very difficult, partially defeating one of the purposes of having the crawl space.

The plastic with the concrete over the top should control the moisture issues coming up from the ground.  The 2 inches of foam insulation under the concrete should help to prevent losing heat to the ground. The concrete should keep critters out and allow using a “creeper” to move around down there.  I haven’t decided on the height, but I’m thinking that it should be three feet.  When on all fours, I am almost three feet tall.  I am 6’3” and it has to be functional.  I would need assistance to figure out how high to make the top of the floor to yield the three feet considering the concrete and foam.

I have not yet discussed this plan with the building inspector.

So Mike, the questions; do you think that this is a good plan?   Would I be able to put in the 2 inches of foam board and the 2- 2 ½ inches of concrete (normal concrete floor being 3 ½ inches) without doing anything different to the splash boards considering that the splashboards are 2×8’s and that there will not be any door thresholds to be worried about?

Stay tuned for Mike the Pole Barn Guru’s answers in an upcoming blog.

Development of My Post Frame Cabin Plans

Thank you to Hansen Pole Buildings’ Designer Rick Carr for today’s guest blog.

Development of my Cabin Plans

I have been looking at both open land and existing “cabins” in the Southwestern part of the State of Wisconsin where I do a lot of fly fishing for trout in anticipation of eventually retiring.  I want to be able to go out and stay for four or five days to a week on short notice without having to worry about where to stay while having my own personal items and gear there waiting for me along with the ability to just fire up the grill for dinner rather than going out every night.  Space for friends bearing Bourbon to visit was also a consideration.

Existing Cabins were disappointing to say the least, either upper level sleeping (which doesn’t work for over 65 year old guys) or tiny showers, filthy kitchens. There was always something very wrong; and all this with a limited budget.  It became clear that building would have to be an option unless I was going to settle in some area or another. With my five year plus experience as a Senior Building Designer with Hansen along with two years on a post frame building construction crew in my youth, I knew that if I had to build, it would be a post frame building.

Last spring I found and bought a nine acre parcel with 1,600 feet of the headwaters of a crystal clear spring creek full of brook trout flowing through.  I have three of the four permits that I need to allow me to put in a driveway and culvert across the creek and the wetlands to the high ground building site on the far side.  The front porch/deck will have great views of both sunrises and sunsets looking over the valley.

Some of the deciding factors for post frame were, knowing that a post frame building can be built to be extremely well insulated for climate control, knowing the cost advantages, knowing the longevity, knowing the framing system, and the fact that I can do a lot of the building myself for additional saving. I have also been developing relationships with the local Amish community who I know that I can hire for reliable economic labor.

About Hansen BuildingsI plan to construct the building so that it can be used as a full time residence for resale value, although that is not my intended use.  Relative to a well-sealed and insulated building, I intend to use BIBS insulation in the walls using 2×8’s in a 7 ½ inch cavity and closed cell foam insulation on the underside of the roof purlins designed for drywall to create a vaulted ceiling in part of the cabin.  This combination will make an extremely tight building making it more comfortable and less costly to heat.

The cost advantages of post frame start with not needing a full foundation and the costs of a full foundation.  Then post frame is very efficient in terms of lumber usage. Over the years I have had client after client send finished building pictures with the tiniest of scrap piles in the background.  My experience and familiarity with our construction manual gives me the confidence that I can act as the general contractor and jobsite supervisor while hiring local Amish builders for more cost savings.  I have a lot of DIY experience so a post frame building from Hansen will allow me to finish most of the interior myself for additional savings.

I am not concerned with how long the building will last, rotting of posts, as some people are because I know that the testing of current pressure treating is good for 70 plus years.  At the age of 66, I will be able to use this Cabin for as long as I can manage, ten to fifteen years, and still have many years remaining of useful life for resale value.

My next consideration was a heating and insulating plan.  My experience as a Building Designer tells me that it is very important to have a heating and insulating plan before ordering a building to make sure that the correct options are designed into the building and are on the Engineer Sealed Plans, especially on a post frame building to be used as a residence.  I have a friend that has a similar building/cabin in the fishing area. A year or so ago on an early spring fishing trip, he asked me to stop in and check on his cabin that was last used back in the prior fall. I walked in and there was no dust, after no one being there for months. I was convinced at that point that I wanted radiant floor heating, but being close to a flood plain, (last year there was a 100 year flood in the valley).

I knew that I wanted a crawl space, which would give a few extra feet of protection in the event of a 150 year flood.  The other advantage is that the crawl space would provide access to plumbing in the event of a problem or change versus having the radiant floor heating and the plumbing encased in the concrete floor. The drawback is that a radiant floor in a building with a crawl space adds other design issues.

Come back tomorrow as Rick investigates his pole barn cabin’s crawl space issues, and asks for Mike the Pole Barn Guru’s wise advice.

Insulation Values Reflect Real-World Energy Performance?

Insulation R Values Reflect Real-World Energy Performance?

Energy efficiency has become huge for post frame building construction. More and more people are discovering post frame buildings as being a cost effective design solution for residential and commercial construction.

Long time readers of this column have seen article after article in this vein, increasing with time. You have also had an opportunity to witness questions from many current post frame building owners who wished they would have designed appropriately to begin with. Proper advance planning can certainly help to achieve desired results.

Let us assume, for a moment, you have created a post frame building with commercial 2×8 bookshelf wall girts and 22 inch high raised heel trusses. In your walls, BIBs https://www.hansenpolebuildings.com/2011/11/bibs/) fiberglass insulation 7-1/4” deep has been used. This will give a laboratory R value somewhere in excess of 30. In attic space, 20 inches of blown in fiberglass will provide a R value of over 60. You have done your work and are happy your decision will give a more than satisfactory end resultant.

Then along I come and poke holes in your investment.

Keep in mind, my very own post frame home has fiberglass insulation very much like our imaginary scenario above.

The most common yardstick for measuring insulation performance will be R value, but there’s a problem. Insulation packaging shows lab analysis of R values, but it’s based upon used testing completely eliminating air movement from results. This matters a lot with fluffy insulation materials because air movement greatly lowers real-world insulation performance. Drafts and air currents often happen within wall cavities and attics and this will be why real-world insulation performance can be significantly lower than advertised values.

Alternatively, insulation products not allowing air movement through them (spray foams and rigid foams, for instance) have real-world insulation values almost identical to what you see printed upon packaging and used in advertising. Their performance doesn’t decline. Air-impervious insulations can be more than twice as effective as air-porous insulations of identical R value under real-world conditions.

Where does all of this leave us as post frame insulation specifiers and building owners?

When I added an exterior elevator shaft to our post frame home two years ago, my insulation choice was closed cell spray foam. I did make an error in that I did not listen to my own inner voice. Our local installer made recommendations for thickness I felt were insufficient, so I had roof and wall sprayed one inch thicker. I should have gone thicker yet as there was plenty of space available to fill. As a result the elevator shaft is cold and drafty into our living space.

Considering closed cell spray foam? Think it may be expensive? Consider its performance will probably be twice as effective as fiberglass and closed cell spray foam suddenly doesn’t seem so costly.

 

Reader Put Up a Competitor’s Shed

We Put Up a Competitor’s Shed

Sadly not everyone does adequate research to realize how outstanding of a value added a Hansen Pole Buildings’ post frame building kit package truly will be. Long time readers of these blog articles (nearly 1600) and questions answered in Monday’s “Ask the Pole Barn Guru™” column (around 1000) have come to understand most problems solved by me come from other people’s buildings.

How serious am I about our value:
I am offering to shop for you. Yes you heard me right. You give me up to three names of competitors to Hansen Buildings, where you can purchase a complete wood or steel framed pole building kit package, and I will shop them to get quotes for you.
Now I say three, because frankly, some people just are not very prompt or cooperative when it comes to getting back with price quotes.

Why would I do this? Comparing “apples to apples”, I know our price will beat theirs, every single time. I am doing this for your peace of mind. I guarantee other prices will be higher. And I will provide you with documentation to prove it!

There is a catch…..before I go shopping, you have to place your order for your new Hansen Pole Building kit….. subject to me “proving my point” by going shopping. Your payment to us will not be processed for ten calendar days. Within seven days of order, you’ll have competitive quotes in hand, or my documentation of having hounded them every week day for a week trying to get pricing for you (seriously, if you have to hound someone for a price, what kind of service will you get after they have your money?).

After I email you proof, if you seriously want to purchase from one of these competitors, just let me know before ten days from your investment and we tear everything up and go away friends.

Ask The Pole Barn GuruReader DAVE in ROBERTS apologizes for buying from a competitor and writes:
“Sir. Your blog has been most helpful. We put up a shed not one of yours but a competitor. (sorry). Shed size is 36×48. First mistake was we did not put a barrier under the concrete. Our plan now is R 19 in walls. One inch of foam plus R 39 in ceiling. I wired in two ceiling fans to move air with natural gas heat. Does this sound like a good formula, oh wise one?

Mike the Pole Barn Guru says:
Start by sealing your building’s concrete slab. This will be a possible solution: https://www.hansenpolebuildings.com/2018/11/siloxa-tek-8505-concrete-sealant/.

I am just not a fan of natural gas heat as it adds a tremendous volume of water vapor into your building. You’re going to have to find a way to exhaust all this water, else your building will have humidity issues.

Although now too late for you, there would have been alternatives: https://www.hansenpolebuildings.com/2016/12/modern-post-frame-buildings-geothermal/.

Let’s discuss your ceiling. I am hopeful you have trusses designed to support a ceiling load of five psf (pounds per square foot) or greater. Also hoping you have ventilation covered with enclosed vented eaves and a vented ridge. Unless you specifically asked for it, your building’s roof trusses probably do not have raised heels to allow for full insulation thickness above walls and in area closest to sidewalls.

Provided your trusses will support weight of gypsum wallboard, install any necessary framing to reduce drywall spans to two feet or less. Place 5/8” Type X sheetrock across bottom of ceiling framing. If you do not have a vapor barrier under your roof steel, spray two inches of closed cell foam insulation across the entire underside. Once you have paid for this, you will regret not having made other condensation prevention decisions.

While spraying foam – have it added to area closest to eave sidewalls (spraying onto top of ceiling drywall). Make certain to leave an inch of airspace minimum above foam, so air can flow in from eave vents. Foamed area should continue towards center of building until it reaches at least a six inch thickness. Balance of ceiling should have no less than R-45 and ideally R-60 of fiberglass insulation blown in.

For walls, I am hoping you have placed a Weather Resistant Barrier (WRB – like Tyvek) between framing and siding. If not, you have a couple of choices. You can remove wall steel from a wall, install a WRB and reinstall steel (repeat for each subsequent wall), or spray two inches of closed cell foam to inside of siding. Unless your building has full thickness bookshelf girts, install framing across inside of walls to eventually support wall finish (I recommend sheetrock). Fill entire insulation cavity with BIBs https://www.hansenpolebuildings.com/2011/11/bibs/.

Glue two inch thick closed cell rigid insulation panels to inside of wall framing, sealing all joints. Glue sheetrock to inside of insulation. Now you have a truly well insulated post frame building.

Metal Building Insulation

Building Has Metal Building Insulation

Hansen Pole Buildings’ Designer Rachel received an inquiry from a client whose existing post frame (pole) building has metal building insulation.

Rachel sent this to me:

“STEVE would like some advice on insulating.  He has a Cleary Building which has blanket insulation in the walls and roof and he would like to insulate over the top of this insulation and wondered if there would be issues.   

Steve mentioned that as your standing in the building you see the white vinyl on the inside.  Is there vinyl on both sides?  If not, shouldn’t the vinyl by facing the steel?

Any information or assistance you can give him would be appreciated.”

Mike the Pole Barn Guru writes:

I am not much of a vinyl faced metal building insulation fan to begin with (read more here: https://www.hansenpolebuildings.com/2011/11/metal-building-insulation-in-pole-buildings-part-i/]. Even though I have it in roofs of my two older personal post frame buildings, it isn’t a product I would use if I were to construct a new building for myself.

Problems would come from having insulation sandwiched between two vapor barriers.

I would do this personally –completing each wall individually, I would remove wall steel, remove  wall metal building insulation. Cover each wall with a Weather Resistant Barrier (like Tyvek) and reapply wall steel. Spray two inches of closed cell foam insulation upon the inside of the wall steel. If full wall thickness bookshelf girts were not used in the walls (flush or extending inside of columns), another set of girts should be added to the inside surface of columns. Your engineer of Record (engineer who sealed your building plans) should be consulted to determine proper size and spacing of girts. Once installed, fill insulation cavity completely using BIBs. Glue two inches of rigid closed cell foam insulation board, taping all seams, to the inside face of girts. Glue interior finish (typically gypsum drywall) to the inside of foam boards.

PBG NOTE ADDED: Hansen Pole Buildings’ Designer Rick Carr aptly pointed out to me WRB (Weather Resistant Barrier) purpose would be defeated by spray foam application. Correct application should be one only, however only after metal building insulation removal.

For your roof, provided trusses are adequate to support applicable dead loads, I would install a truss bottom chord level ceiling. This would allow insulation to be blown into dead attic space. In order to achieve adequate insulation above the sidewalls, it may prove necessary to use closed cell spray foam insulation above the ceiling in areas closest to the sidewalls. If eaves have ventilated soffits, ensure an inch or more of free air space exists between insulation and roof deck (or metal building insulation). Appropriate ventilation must be provided in dead air area above insulation.

 

Net Zero Post Frame Homes

Net Zero Post Frame Homes

Energy efficiency has become a huge focus in every type of home construction. Post frame homes can be net zero, just as well as stick frame.

Our environmental commitment allows us to design post frame homes to reduce environmental impact. High performance design and advanced engineering make it easier and more attainable to build a home producing as much energy as it needs through renewable energy, known as net-zero energy.

A net-zero home will be more than a house with solar panels. It’s a house designed to put energy conservation first: from framing to finishing. An airtight structural shell paired with additional options – such as highly insulated wall systems, high performance windows, passive solar design and more – mean any Hansen Pole Buildings’ post frame home can be designed to achieve net-zero energy.

Reader IAN from MIDDLETON writes:

“Mike-

First, I want to let you know how much I have enjoyed reading your blog. I started reading through it topically to answer some of my questions, but because I have been finding so much good information, I resolved to start at the beginning and read through chronologically to make sure I don’t miss anything. Thank you for sharing your lessons learned from decades of experience.

I’ve been exploring options for a cost effective and energy efficient single family home. Reading on your blog has convinced me of the advantages of post frame construction, but I have also been reading about ways to achieve high energy efficiency. In particular, I’m interested in ways to incorporate thorough air sealing and extra insulation (in particular for walls) into a post framed structure. I have found numerous references on the internet to the ways that post frame construction is generally moderately more energy efficient that stick framing, but I have only found a few examples that specifically address trying to achieve a very high level of energy efficiency in a post framed house. The clearest example I’ve found is the following short video that profiles the construction of a net zero single family home in upstate New York: https://youtu.be/PKXNwdvUNj4

My questions for you:

Have you designed a post framed home with high energy efficiency in mind? What kinds of strategies did you use to achieve high energy efficiency?

Have you ever designed a super-insulated post framed home, and if so, how did you incorporate the additional insulation? Some approaches used in stick framing are double stud exterior walls, or supplemental rigid foam insulation between the sheathing and siding (likely not ideal for a steel clad post framed building). Have you seen these or other super-insulation strategies used on post framed buildings?

Finally, have you ever had a post framed home blower door tested for airtightness, if so, how did it perform? Do you have any recommendations for air sealing strategies specific to post frame construction?

Thank you for considering my questions; keep up the good work!”

Thank you for your kind words. Sadly, most post frame home clients are just not savvy enough to be willing to make an extra upfront investment to super insulate their buildings.  I have designed several post frame residential buildings for my own use, so I have learned from mistakes. Also, technologies have improved greatly in recent years, making energy efficient designs more practical.

For walls, my current best recommendation would be to use two inches of closed cell spray foam against siding insides. Walls would be framed with bookshelf style girts to create a deep insulation cavity. BIBs insulation would be used to entirely fill the wall cavity. Inside of the  girts, covering columns as well, two inches of rigid closed cell foam board would be applied with glue, and all seams sealed. Gypsum wallboard (sheetrock) would be then glued to the foam board. Using rigid foam board inside eliminates any thermal bridging as well as creating a vapor barrier.

With 2×8 bookshelf girts, a wall system of over R-50 could be obtained using description above.

I am not yet sold about creating a warm attic – so I’d use 22 inch raised heel trusses and blow in 20 inches of fiberglass to go R-60 and beyond.

I haven’t seen any post frame air tightness tests, however even 25 years ago (when I was building post frame buildings) we had instances where our post frame homes and commercial buildings were so tight, a window had to be opened in order to close exterior entry doors!

Good Luck! And let me know how it all turns out. I’d love to see pictures of your progress!

 

Do I Need Any Additional Vapor Barrier?

Do I Need Any Additional Vapor Barrier?

Reader TOM in NEW LONDON writes:

“Have a 40 x 60 pole barn which I have poured a 20 X 60 6″ concrete floor with radiant heat. I have installed 1 1/2″ R 7.5 rigid pink board between the 2 X 6 side boards against the steel. I will be installing R 19 kraft faced insulation in the 2 x 6 side walls and R 38 kraft faced insulation in the ceiling. The area above the ceiling insulation is completely open to the roof.  Eaves soffit is vented. Do I need any additional vapor barrier? Have I done anything wrong?
Thank you.”

Some basic commentary, from your photo, to begin with. I obviously do not have the benefit of having your building’s engineered plans or sealed truss drawings to reference, so some of my commentary will be based upon best guesses.

I would sincerely doubt your building’s roof trusses have been designed to support loads induced into them from knee braces. Please read more in regards to this subject here: https://www.hansenpolebuildings.com/2012/01/post-frame-construction-knee-braces/. Your first step should be to contact the truss manufacturer to verify ability of your building’s trusses to withstand loads from knee braces. With an assumption trusses were not so designed, second step will be to contact the engineer who designed your building to find out if your building will still be structurally sound with knee braces removed. If, by some chance, an engineer was not engaged to produce your building plans, a competent one should be retained to do an analysis of your situation.

Any lumber in contact with concrete needs to be pressure preservative treated – this would include plates between columns and bottom plate of your framed stud wall. You really do not want to have these boards decay within finished walls.

If you do not have a well-sealed vapor barrier beneath your concrete slab-on-grade, you need to use a good sealant over top of it.

Moving forward, to your question at hand. In order to install kraft faced batts along your building’s sidewalls, you will need to add additional framing. Most folks place another set of wall girts upon column insides. If so, in your case, then R 19 batts are not going to be adequate – as they will leave an air gap between batts and pink board. My recommendation would be to use BIBs (https://www.hansenpolebuildings.com/2011/11/bibs/) in walls, with a vapor barrier to inside face of framing before adding the finished wall material. To get best thermal performance, a layer of closed cell foam insulation board can be glued to wall framing inside, then glue gypsum wallboard (sheetrock) or your choice of other products to insulation boards. This inner layer of foam board, if joints are sealed, will act as your vapor barrier. Have your building engineer confirm your building walls will be stiff enough to keep drywall joints from cracking.

Now – roof system. Before adding a ceiling, verify your building’s roof trusses will support this added weight. Most post frame building trusses will not! Trusses should have a minimum bottom chord dead load of five psf (pounds per square foot) to support framing and drywall. Your building does not have a vapor barrier between roof purlins and roof steel. Only cure for this now will be to have two or more inches of closed cell foam insulation sprayed to the underside. If you fail to do this, you will have moisture/condensation issues in your attic. You also do not want to have a vapor barrier in your ceiling line – so kraft faced batts are out. I’d recommend 15-20 inches of blown in fiberglass insulation. Make sure to not block air intake from soffits. If your ridge cap isn’t currently vented, it needs to be.

 

Tom could have avoided a great deal of pain and expense had he and his building provider been communicating in regards to climate controlling this structure. Unfortunately, most post frame building kit suppliers and contractors are focused only upon providing a low price, instead of best design solution for their clients.

 

 

Mixing Tyvek and Radiant Reflective Barrier

Mixing Tyvek and a Radiant Reflective Barrier
Reader JOHN in PENNSYLVANIA writes:
“Hi, My name is John and I have been reading the blogs and questions from prior customers.  However I have one of my own that has not been asked or that I can see has been answered.  I my pole barn I am putting Tyvek barrier between the outer metal siding and the horizontal 2×4 girts going from post to post.  I am insulating my building as I am making it into a butcher shop at some point.  I want to put the double bubble foil on the interior side of the girts, however I do not know if the Tyvek barrier would overheat in the summer and cause a fire or shrink.  Have you seen anyone do this and would you recommend it.  The reason I want to use the double bubble foil wrap inside is to reflect the radiant energy away from the parts of the building I want to keep at a constant 40 degree temp without having to super insulate everything.  I planned on using a r-30 insulation or blow it in like you guys suggest on your web site.  Any help would be appreciated.  Thanks.”
In my humble opinion, what you propose should not harm the Tyvek, however there are some other considerations.

Mike the Pole Barn Guru answers:

First – a reflective radiant barrier is a vapor barrier. You are creating a cavity in which moisture will be able to be trapped between two vapor barriers in your wall – not a good choice.

Second – the reflective radiant barrier is defeating the purpose of the Tyvek – which is to allow any moisture in your wall to pass through to the outside.

Reflective InsulationThird – if you insist upon using the reflective radiant barrier, single bubble will do everything double bubble will, at less cost.

My recommendation for your walls is to install another set of girts flat wise (barn style) on the inside of the columns. Use BIBs (https://www.hansenpolebuildings.com/2011/11/bibs/) to completely fill the wall cavity with insulation (the money you save from eliminating the reflective radiant barrier will pay for it). Install a clear visqueen vapor barrier on the inside, then your choice of interior finishes.

Insulating a Post Frame Home Crawl Space

One of our clients has been erecting a post frame home in Colorado Springs, which is over a crawl space. Here is our discussion in regards to insulating the crawl space.

“While I have your ear, I had asked you a question earlier about getting the code required R30 in the 2×6 floor joists of my raised floor. I looked into your suggestion of spray foam and I got some quotes from local companies and I was shocked! One company quoted me $16,000 to do 3″ in the floor and walls with some performance charts showing that the 3″ would satisfy the code (I’m a bit skeptical). I got another general quote of $1.10/board foot and that it would take 5″ (i.e. $5.50 / sq ft)  or $12,650 just for the floor. The second company did suggest though that El Paso county allowed the R30 around the crawl space perimeter and no insulation in the floor… which leads me to my question…

What would be your thoughts of a non-vented crawl space using something like 15 mil plastic on the ground and up the sides the 18″ to the floor and the R30 spray foam from the ground to the floor level?  I could get that done for around $2500. I’m still haven’t completely decided if I will used dense pack cellulose or BIBs for the walls but I’m pretty sure I don’t have the budget for spray foam in the walls.”

Mike the Pole Barn Guru Responds:

When I moved to Oregon from Eastern Washington in 1979, I was amazed at how different the construction techniques were from what I had grown up with. Eastern Washington was the land of full basements, whereas Western Oregon was predominately crawl spaces. The typical crawl space would have 6 mil black visqueen draped down the sides of the foundation and covering the ground, with R-19 unfaced batts used to insulate directly beneath the floors.

A variant of this was to use the crawl space as an air plenum, eliminating the need for heat ducts, and placing the unfaced insulation against the foundation.

This variant is basically a very slight spin away from what you propose to do.

Performance charts always frighten me as they general require some hocus pocus involving dead air space. Closed cell spray foam is R-7 per inch, so a claim of three inches in a system making R-30 sounds bogus unless the balance of the cavity is going to be filled with something like unfaced fiberglass batts. There is no question about closed cell spray foam being expensive, even the work I had done when we added the elevator shaft on the back of our home ran $2.80 per square foot for four inches thick.

Personally, I have no issues with what you propose to do and would probably take it a step further and utilize the principles of Frost Protected Shallow Foundation insulation below the base of my wall steel. https://www.hansenpolebuildings.com/2016/11/frost-protected-shallow-foundations/.

How Insulation Works

I so enjoy clients who truly care about the outcomes of their post frame buildings. In this case, I’ve been back and forth with reader Eric and today we are discussing how insulation in walls works.

Eric writes:

“Mike,

Thanks again for the input. I read those articles you mentioned on the BIBs and the white liner panels. The liner panels are very common and popular around here but the article had very good points and gave me more to think about. As for the insulation, I was not familiar with the BIBs system and was impressed. I have done some more reading and reached out to a few contractors for quotes on the BIBs system. I do prefer to do things myself whenever possible however, so the option of installing fiberglass myself is still on the table. This is where I still have a question. You mentioned to fill the entire wall cavity with unfaced fiberglass and then cover with Visqueen. Is there an issue if the cavity is not completely filled and an air space is created between the fiberglass and the Tyvek® behind the metal sheeting? I ask because my walls are roughly 5 1/2” deep and obviously R13 is only 3 1/2” thick and R19 is 6 1/2” thick. If I go with R13 (cheaper) I end up with an air space. If I go with R19, I end up compressing it and losing r value anyway. Also, I have diagonal bracing in the corners which will also make it near impossible to tightly fill with fiberglass batts. I would love to go with the BIBs system but am waiting to see if it is within budget. If I can save considerable money insulating myself with batts I would most likely do so but need to be sure I am not causing problems down the road. Sorry for being so long winded and thank you very much for all your help and information.”

Mike the Pole Barn Guru responds: How Insulation Works

Fiberglass itself has little resistance to heat flow. The actual insulator is the air trapped in the tiny spaces between glass fibers. The tiny air voids slow conductive heat movement, while the glass fibers reduce radiant losses and impede air movement to block convective heat flow.

Don’t be fooled by so-called dead air spaces. Small air voids slow heat flow, but large voids don’t. A dead air space is one in which air does not move — once a gap gets larger than 3/4 inch, convection kicks in and overrides the insulating effect. Even though they contain air, uninsulated framing cavities have little or no R-value.

Making contact.

This understanding should govern the way batts are installed in the field. They should make good contact with wall and ceiling and nestle snugly against the sub-floor at the base within wall cavities. If the batts don’t touch the inside face of the drywall and the housewrap, convection coupled with air leakage will seriously undermine their thermal performance. Use only unfaced batts in exterior walls, because we’ve found inset stapled kraft-faced batts tend to create gaps between the insulation and the drywall. (Using unfaced batts also prevents the drywallers from complaining about the presence of stapling flanges on the surface of the framing.)

In other words, even though shoving batts into a wall girt cavity may seem like a no-brainer, doing it right takes some care. If a batt is simply jammed into place, its edges tend to drag along the sides of the girts on either side, which often prevents the rear corners of the batt from coming into contact with the exterior sheathing.

Moral of the Story

If your budget does not include closed cell spray foam insulation, then BIBs is a great solution and is effective.

How to Insulate My Post Frame Garage

How to Insulate

I fear “how to insulate my post frame (fill in the blank)” is going to be my most answered topic for the next decade. Energy efficiency is the “hot” topic right now and sadly there are more folks trying to solve what they already have, than there were those who planned for it correctly in the beginning.

Reader ERIC in FENELTON writes:

“Hello, I am wondering what the best and most cost effective way to insulate my post frame garage would be. I recently erected a 32’x48’post frame garage with glulam posts on 8’ centers, girts and purlins on 2’ Center’s, trusses on 4’ centers with 1’ overhangs with center soffit and ridge vent. Walls and roof are steel with double bubble between purlins and roof steel and tyvek between hurts and the wall steel. I will be building a wall to separate one of the bays as a metal shop for welding and fabricating. This will be the only bay that is heated and is 32’x21’. I am on a budget but my biggest concern is moisture. I installed the tyvek and double bubble hoping to positively effect the problem but am still hesitant to put fiberglass in the
walls but spray foam is out of my price range. I have seen some people cut 1 1/2” foam board to fit between the wall girts and either stop there or then frame traditional walls between the posts and add R13-R19 faced insulation. Is this an adequate way to insulate and will the foamboard keep moisture from the fiberglass? I will definitely be framing between posts and then covering with painted OSB regardless of the insulation method I choose. Also, I was leaning toward using fiberglass batts in the ceiling and then using the white liner steel under the trusses. They are 2×6 top and bottom cord trusses and rated for a ceiling. Fiberglass in the ceiling gives me the same moisture
concerns however. So I guess my question is, now that you know about my building, what is the best abs most cost effective way to insulate the portion of the building and avoid moisture? Spray foam is out of the question due to costs. I have been doing a ton of research but get different answers everywhere I go. Any help will be greatly appreciated. Thank you.”

Mike the Pole Barn Guru
As long as the Tyvek is well sealed, you will not be gaining moisture from the outside on the walls. What you need to create is a dry wall cavity. Completely fill the wall with unfaced fiberglass (you might consider using BIBs https://www.hansenpolebuildings.com/2011/11/bibs/)
and cover the interior of the wall with a well sealed vapor barrier (clear visqueen will do nicely). Cutting foam board is an exercise in
futility unless you can figure out how to completely seal it, if you
stop at this point.

For your ceiling – there is a good chance you will experience
condensation on the underside of the steel ceiling liner panels. With
your vented eave and ridge, blown in fiberglass is probably the best
answer. If you do not have raised heel trusses, you should probably look
at spray foaming the first couple of feet of the ceiling area in order
to reduce heat loss from not being able to gain full thickness of the
fiberglass.

BIB’s Insulation, In-Ground Posts, and Rodents

BIB’s Insulation, In-Ground Posts, and Rodents

DEAR POLE BARN GURU: I’m still in processing with the county to get permits for our new Hansen home building but in the meantime I’m trying to figure out insulation for our raised floor. County requirements (I’m assuming IBC code) requires R30 floor insulation. The building floor design wound up using 2×6 floor joists so I’m trying to figure out how to get R30 worth of insulation in a 2×6 joist cavity? I’m planning on either BIBS or blown/dense pack cellulose for the walls and ceiling and there’s no problem there, but the floor is an issue. I’d rather continue cellulose or BIBS in the floor but I’m not seeing a clear solution( I can do spray foam if absolutely necessary but I’d really rather not). Do you have any suggestions? LONNIE in COLORADO SPRINGS

DEAR LONNIE: I know you have read my blogs, so you know I am a huge fan of BIBs, having used the system in two of my own buildings. I previously have had some qualms about the use of closed cell spray foam insulation, however my physics teacher son had good results with it in the remodel addition to his home, so we used it when we added the elevator shaft to the rear of our own home and I am now a convert. You can get R-30 with as little as four or so inches of closed cell spray foam and it absolutely seals up everything.

 

 

DEAR POLE BARN GURU: I will be building a post and beam barn (40×48 or thereabout) on my property and would like a central loft that I can finish for additional living space. I have been advised that posts concreted into the ground are unlikely to last but I’m a bit concerned about a two story structure with posts bolted to concrete piers… What would you normally recommend? MIKE in LEXINGTON

DEAR MIKE: Whoever is giving you the information about the lifespan of properly (key word being properly) treated pressure preservative treated columns not lasting, knows not what they are talking about.

I personally own three multistory post frame buildings, including our home which has 8000 finished square feet and a roof peak 44 feet above the ground. Every one of them has treated columns in the ground.

While columns bolted to piers will work in most situations, why go to the expense and extra efforts?

 

DEAR POLE BARN GURU: I was wondering if you had any ingenious ideas about how to keep mice coming in from sliding barn doors? We have stuffed steel wool and sprayed foam into the corrugated hollow sections of the walls but they’re still able to come in through the gaping hole under the sliding door.  Any ideas how to resolve that? MELANIE
carport barnDEAR MELANIE: I always warn people who are planning on using sliding doors – as long as you do not mind your neighbor’s cat getting into your building, they are great. No matter what you do with a sliding door, short of affixing it so it will not open, the mice are going to get in. An adult mouse only needs a hole the size of a dime in order to enter your building. By its nature, the sliding door needs to do one thing to function – slide, and in order to slide it has to have space to be able to clear the members which are under it. If your building does not have a concrete slab on grade floor, you could pour a concrete curb across the door opening, however the bottom of the door will still need to be adjusted up high enough to clear the concrete given the fluctuations in expansion and contraction of both the door and the building due to seasonal changes in temperature and humidity.

If you truly want to eliminate the problem, replace the sliding door with an overhead door. In the meantime, it might behoove you to invest in a good barn cat or two.

 

Post Frame Insulation in the South

Post Frame Insulation in the Hot and Humid South

Reader RICK in LUCEDALE writes: Dear Pole Barn Guru, I am in the planning stage for designing a post frame house. I live in a “Hot and Humid” climate in the southern US. Joseph Lstiburek, a building science guru, suggests having an unvented roof for my climate zone with the HVAC in the conditioned air space. The metal roof would have a layer of single bubble vapor barrier under it with BIBS insulation installed in the roof purlins. The walls would have a building wrap behind the metal siding and BIBS insulation. The walls would have a vapor barrier between the drywall interior and the insulation. Does the roof assembly need another vapor barrier on the inside? What happens at the intersections between the single layer bubble vapor barrier, the building wrap, and the sub slab vapor barrier? I assume I can use non venting closure strips at the ridge and closed non venting soffits? What size should the purlin be to get an R value of 30+ ? What would be your recommendations? Thanks.”

Mike the Pole Barn Guru writes:

Unless your post frame house will have extremely large purlins, you will not be able to get sufficient depth of insulation using BIBs. Energystar.gov recommends roof insulation values of R-30 to R-60 for your part of the country. BIBs provides an R value of 4.23 per inch, so to achieve a minimal value of R-30 would require at least a 2×8 purlin and would realistically not provide the insulation value I would personally be looking for.

I’d be looking at the use of closed cell spray foam insulation, which would give you R-7 or better per inch of depth. It also completely seals everything, eliminating the need for a reflective barrier below the roof steel. With 2×6 purlins, one could spray eight inches of foam completely filling the space between the purlins as well as covering the underside of them (and the underside of the roof truss top chords).

The goal here is to achieve a complete envelope seal of your building’s perimeter. You will not want a vapor barrier between the living space and the attic. The building wrap is not a vapor barrier, it is a weather barrier. The vapor barrier on the inside of the walls should be installed so as to be sealed into the roof plane spray foam and sealed tightly to the slab on grade (although I prefer living over a crawl space).

Soffits should be non-ventilated and closed cell foam closure strips should be used at the top and bottom of all steel panels.

Insulating an All Wood Gambrel Barn

A reader writes: “Dear Guru.I have an all wood gambrel style pole barn that I’m converting to a shop.  I’ve installed forced air heat and am getting ready to insulate.  My exterior walls are Tyvek wrapped osb and vinyl sided.  I am wanting to use rigid board to help deter rodent nesting.

  My questions are: for the walls should I cut and fit 1 1/2 inch board to fit all of the spaces between my girts before I layer rigid over the girts or can I layer over the girts to start?   The ceiling I was planning on installing 2″ rigid on top of the 2×4 truss bases and then applying a closed cell poly “Prodex” brand white faced on the bottom leaving the 3 1/2 inch air gap between the two. Prodex is claimed to be r16 and the rigid r10. Or is there a more suitable way to do the ceiling like cutting board to fit between said trusses and using Prodex on bottom with no air gap?  

 Thank you for your help.  I’m finding hundreds of articles and advice on metal buildings which mine is not and trouble finding a solution for my project.  Oh, and I live in northern Ohio”

Good move having Tyvek in your walls to prevent weather from seeping into your insulation cavity. If your walls are tightly framed (which they should be) the possibility of rodents getting into your wall cavities should be zero. Cutting and fitting insulation board to fit between framing members sounds like a mountain of labor, as well as pretty near impossible to be able to get a tight fit against every stud. I’d be inclined to use either closed cell spray foam insulation or BIBs insulation for walls.

Prodex is a radiant barrier and your chances of getting a measurable R value out of it more than one and change is not good. In a thorough 2010 study by the Canadian National Institute for Research in Construction, their conclusion: In a perfect state (with no dust on the surface), a radiant barrier with an air gap increased the efficiency of insulation in a wall by 10%. In other words, if the wall was already R6, adding ‘miraculous’ foil bubble wrap added .6, for a total of R6.6.

The best way to insulate your ceiling is to blow in cellulose or fiberglass to at least R45, if not R60. Do not place a vapor barrier under blown in insulation. Make sure the attic space above the insulation is adequately vented.

 

Mike the Pole Barn Guru

Post Frame Antiperspirant- Ventilation Frustration

This is a sad story I hear all too often from pole (post frame) building owners who have buildings which were not properly designed for future uses, especially when it comes to insulation and ventilation.

Reader JASON in TENINO writes:

Hi Pole Barn Guru,

I recently purchased a new house and it came with a 40×60 shop. This past year I’ve experienced terrible slab sweating every time there is a change in humidity. Now that it’s summer I would like to prevent the sweating from occurring again. What are my best options on a limited budget? I’ve looked into using a penetrating concrete sealer, but I don’t think that addresses the underlying condensation problem.

As far as I can tell the shop has no ventilation of any kind (ridge/gable/soffit). And I’m noticing black mold starting to develop in the insulation below the roof. And I’m not sure if any sort of vapor barrier was placed before the slab was poured.

In the future I would like to insulate and heat the shop, but for now, I’d be happy if I can stop my condensation problems.

Thank you for your help!!!

DEAR JASON:

Yep – you have a problem on your hands. I can pretty much guarantee there is no vapor barrier under your concrete floor, which is a shame someone cheaped out. Vapor barriers are so inexpensive.

Taking care of first things first, let’s get the floor sealed. Here is the information you will need: https://www.hansenpolebuildings.com/2012/07/concrete-sealer/.

Secondly – get rid of the mold. Mix in the ratio of one cup bleach per gallon of water and use a hand pump sprayer to saturate all moldy surfaces. You can also use a scrub brush to remove the existing mold.

Third – I am going to leap ahead to your future plans, as they will impact your solutions now. I am not a gambling man, but I would put money on your shop’s trusses not having been designed to support the weight of a ceiling. This means if you want to eventually insulate and heat the building, you will have to insulate above the bottom chord of the trusses and up the roof line. On the walls, you can frame in either with a stud wall or with bookshelf girts to create a method to support insulation, with either batts or BIBs (Blow in Blanket) insulation being the most cost efficient and effective for your investment dollars.

Insulating the roof, not so easy, as the only really practical solution will be to use closed cell spray foam between the roof purlins. You will want to consult with an installer to get their opinion as to whether the metal building insulation under the roof steel will have to be removed prior to spraying.

If you are going to spray foam, then you do not want to use a ridge vent, as the foam would cover it.

Here is my best advice (provided you have the space on your property) – use your existing building only for cold storage. Since you do not have vented sidewall overhangs to create an air intake, the only solution for ventilation is to use large vents in each endwall. At a bare minimum, you should have at least 576 square inches on net free flowing vent in each end – located in the top half of the gables. You may need to add power vents, in order to adequately move the moisture out of the building.

When your budget allows for some climate controlled space, construct a new building which is properly designed to be able to be energy efficient.

Here is a short list of features which you should include:

Underslab vapor barrier
Pex tubing in slab for in floor heat
Perimeter slab insulation (rigid foam)
Bookshelf wall girts to create an insulation cavity
Housewrap between wall girts and siding
Vented sidewall overhangs
Ceiling loaded trusses with ceiling joists
Raised heel trusses to allow full insulation depth from wall to wall
Blow in R-45 to 60 of ceiling insulation
Reflective radiant barrier between purlins and roof steel

Good luck and let me know how things turn out!

Mike the Pole Barn Guru

Spray Foam Insulation with Dupont Tyvek House Wrap

Hansen Pole Buildings Designer Rachel asked me about this today:

“I have more and more builders say they put Tyvek® on the walls and roof and then spray foam.  This is so they can replace the siding/roofing in the future.  Do you find any downfalls with this?  I thought this was a pretty good idea.”

Having just written an article about spray foam insulation (https://www.hansenpolebuildings.com/2016/07/advantages-spray-foam-over-batt-insulation/), this is a well timed question.

Tyvek and all house wraps are NOT (I repeat NOT) vapor barriers. They are weather barriers: https://www.hansenpolebuildings.com/2016/01/determining-the-most-effective-building-weather-resistant-barrier-part-1/.

Spray-Foam-Insulation-150x150In doing my research on the whys and why-nots I found apparently there are some spray foam insulation contractors who will not spray foam against house wraps, apparently from not being able to guarantee their product would properly adhere to the house wrap.

In one particular case – the spray foam insulation contractor tried to persuade the client to use BIBS® insulation (read about BIBS® here: https://www.hansenpolebuildings.com/2011/11/bibs/) due to the potential adhesion issues.

There apparently is an adhesive additive for spray foam, which will assist in the foam being able to stick to house wraps or other slick surfaces.

As spray foam is a vapor barrier, and is resistant to moisture passing through it in either direction, adding a weather barrier to the outside becomes redundant.

If the idea is to use a product to allow for easy residing or reroofing, then a product such as clear visqueen (https://www.hansenpolebuildings.com/2013/07/moisture-barrier/) might prove to be as effective, as well as less costly than a weather barrier. This is, of course, providing the spray foam installer is willing to spray over it.

As a good, high quality steel roofing and siding should last the life of the building – installing any product between it and the siding, under the premise of making future replacement easier, it sounds much more like someone trying to make a feature into a benefit, than it does something which will add value to the client as a benefit!

Pole Building Insulation Once Constructed

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: I want to insulate my already constructed pole building that has 10′ center uprights 8.6 in between uprights 16′ sheathed ceiling’s uprights are 5.5″ diameter what’s the best most cost effective way to go about it. MARK IN CAMBRIDGE

DEAR MARK: I’m going to have to do some guessing as the math doesn’t quite work out. If your “uprights” are on ten foot centers then the space between the columns will be 9’6”. If the space between is 8’6” then your columns are nine foot on center.

Ceiling will be easy – as long as you have a thermal break (e.g. reflective radiant barrier or similar) insulation can be blown directly on top of the ceiling. If no thermal break has been provided, then a layer of spray foam insulation should be applied to the underside of the roof steel.

Adequate attic ventilation will need to be provided – read more about it here: https://www.hansenpolebuildings.com/2014/02/pole-building-ventilation/

For the walls, the first step – remove the wall steel, one wall at a time. Install a good quality building wrap (https://www.hansenpolebuildings.com/2012/11/house-wrap/).

How the inside is handled will be based upon the materials being used on the inside of the wall. For materials which will not crack (steel liner panels, OSB, or plywood) 2×4 wall girts can be added to the inside of the columns “barn style”.

For sheetrock, things get a little more dicey, as the original design of the building should be checked by a RDP (Registered Design Professional – engineer or architect) to verify the building is stiff enough to keep deflection within allowable limits. Provided the building is adequately stiff, 2×4 or 2×6 wall girts can be added “bookshelf” style (https://www.hansenpolebuildings.com/2011/09/commercial-girts-what-are-they/).

Once any electrical work has been completed in the walls, unfaced batt or BIBs (https://www.hansenpolebuildings.com/2011/11/bibs/) can be added to the wall assembly. A well-sealed vapor barrier needs to be placed on the inside of the wall insulation https://www.hansenpolebuildings.com/2013/07/moisture-barrier/.

DEAR POLE BARN GURU: Have you ever tried using stands under your posts before you pour. I like the concept brand “X” uses, just seems a little overly complicated.

Thanks. SCOTT IN MACOMB 

DEAR SCOTT: Without knowing who Brand “X” is, hard for me to comment on their methodology. I have not personally tried the use of stands, however I have written about them: https://www.hansenpolebuildings.com/blog/2014/05/one-pour-reinforcement-cage/.

This does seem like a costly method, when it is actually quite simple to just ‘float’ the posts in the holes: https://www.hansenpolebuildings.com/blog/2015/04/floating-poles/

Mike the Pole Barn Guru

DEAR POLE BARN GURU: Can a pole barn be designed for a crawl space instead of a concrete slab? SUSAN IN OPELIKA

DEAR SUSAN: Most certainly. As we are seeing more and more people gravitating to pole barn (post frame) technology for dwellings, we are designing more homes over both crawl spaces and full basements. We design pole buildings for folks with crawl spaces quite frequently. You can read more about pole barn crawl spaces at: https://www.hansenpolebuildings.com/2013/03/crawl-space/. Or, if a crawl space isn’t enough, a basement: https://www.hansenpolebuildings.com/2013/04/basement/.

Mike the Pole Barn Guru

DEAR POLE BARN GURU: I have been planning a 24 x 48 x 10 three sided barn as it fits my needs for equipment storage and heat build-up and natural light. I read your blog on 3 sided barn vs. wind. My barn would be enclosed on the long north wall and the short east and west if I left open the east wall would that be enough to alleviate the wind pressure concern.
Thanks. BUDD IN MARIANNA

DEAR BUDD: From reading my article on three sided buildings (https://www.hansenpolebuildings.com/blog/2014/03/three-sided-building/), you have found out it may not be the most economical design solution.

Ideally, you would be able to construct a four sided building. The three sided design works fine structurally, as long as it is properly designed to resist the added loads. If you leave a long side and a portion of one of the other walls open, then you could reduce the wind pressures. In any case, I would recommend you seek out the services of a firm such as Hansen Pole Buildings – who can arrive at a solution which is structurally sound and best meets your needs.

Mike the Pole Barn Guru

How Long Will a Pole Barn House Last?

DEAR POLE BARN GURU: How long will a pole barn house last? Should I pour concrete in with the poles? Should I put sleeves on the bottoms of the poles? Question from Karen Sasakwa, OK DEAR KAREN: A properly treated pressure treated timber should outlast the lifetime of any of us here on the planet today. https://www.hansenpolebuildings.com/blog/2012/10/pressure-treated-posts-2/ This means plan on a properly designed pole barn house being around for generations. For the sake of preventing settling, uplift and overturning concrete should be poured around and below the base of the treated columns. https://www.hansenpolebuildings.com/blog/2013/02/concrete-pier/ We can provide plastic sleeves, however the huge majority of new building owners do not use them. https://www.hansenpolebuildings.com/blog/2012/04/plasti-sleeves/

Mike the Pole Barn Guru

DEAR POLE BARN GURU: I have built a 30x40x18. Installed a 6mil vapor barrier on bottom of trusses and a steel ceiling. I blew loose fill r48 in an attic with 2×3 gable vents, ventilated ridge cap “flexovent” and vented soffit.

Now for the walls Tyvec on all exterior walls between girts and exterior panels. I want to wainscot the interior walls to 8′ and finish above w/white poly laminated fiberglass custom manufactured to fill pole voids starting at a nailer girt at the top of the liner wainscot. The grade board is insulated w/2″ pink foam and the same is custom cut and placed on the slab to finish flush with the interior nailer girt to isolate the slab from whatever I insulated the wainscot wall with.

Now my question? I was thinking about filling the cavities in the walls w/cellulose loose fill and possibly tamping it or vibrating it to maybe to achieve some compaction? To slow settling and per industry standards install it correctly. I would use filler strips at top and bottom of all panels to eliminate loss. The fiberglass could always be unattached from the nailer at a later date and more added if settling creates an open space between the glass and the cellulose? My question should I place a vapor barrier between the steel liner panels and keep it continuous with the poly vapor barrier on the glass above it? And will this work? Don’t be afraid of new ideas and just recommend glass behind the wall panels. I don’t like the voids glass always creates in profiled panels with diagonal girts.

Thanks Mark, Ohio City, OH

DEAR MARK: There might very well be an easier way to get maximum R value and fill all of the voids using fiberglass insulation – BIBs. You can read all about it right here: https://www.hansenpolebuildings.com/blog/2011/11/bibs/

My wife and I used it in for our pole barn house and it has performed better than we anticipated for heat/cooling loss.

DEAR POLE BARN GURU: I have an older home with a huge attached garage. I am looking to add a laundry room/bathroom to the garage however wanting it to look original. My home is on a crawl space as well. Could I do a pole barn structure inside the garage? Positive and negatives would be great as well. Cameron in Lima, OH

DEAR CAMERON: Could you? Certainly, however as much as I love pole barn (post frame) construction, building a pole barn structure inside your huge attached garage is probably an overkill. As these interior walls will be non-structural (not load bearing) it would be the most economical to frame 2×4 stud walls with a pressure preservative treated bottom plate.

Mike the Pole Barn Guru

Shop Insulation

I really enjoy the Hansen Pole Buildings’ Designers. They honestly want to know, and in our industry there is a lot to know. A typical day for a Building Designer can run the gamut from the farm, to the office, home or the store as well as enjoying clients from everywhere in the country.

BInsulated Buildinguilding Designer Doug asked, I’m sorry to keep beating the insulation horse, but I have a client who wants to put up a 60×100 building on his timberland. I asked him about heating it and he wants to put a wood stove in it. So he wants to heat it occasionally. It’s in Clackamas County, OR, so it will get cold. 

 If this were your building and you wanted it to be cost and wood-stove effective, what would you do?

 I’m tempted to give him one quote with reflective roof insulation and house wrap, and one with full batt insulation. Am I going down the right road here?

 Thank you for your help.”

 I so appreciate being asked how I would do something. Me – I am frugal, but I will do it right. And most aesthetic elements of pole buildings also have a function and add value for the investment.

My response to Doug: I rarely heat mine, but I did it right, so no one will ever need to mess with it. And the resale is huge from a well done garage.

Me (this is exactly what I did too)….I would commercial girt the walls, use housewrap on outside and BIBs insulation on the walls; ceiling – ceiling load plus ceiling joists, raised heel trusses (means eave height needs to be taller), vented overhangs & ridge, blow in R-60 fiberglass over 5/8″ Type X drywall.

I didn’t do it just because I could, or could afford it – it was about doing it right.”

 Read more about climate control here: https://www.hansenpolebuildings.com/blog/2012/04/climate-controlled/

 The cost of a building, is in deciding to do it at all. Once this hurdle has been crossed I always encourage clients to build the largest building which is economically feasible and will fit on your site. You only get one chance to do it right or wrong – please, if at all possible do it “right”.

Scissor Trusses Economy

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: Hi,

I recently built myself a pole-barn home in NY that used the traditional flat girt style with columns 8′ OC and a double 2×10 truss header and trusses 4’OC.

The overall result has been great as we have achieved net-zero energy with our all electric utilities and solar PV array.

I’m thinking of getting into the home building business and want to use the post-frame technology to deliver the most affordable and highly-engineered product.

After reading your site, I’m totally sold on the double truss system and 12′ OC truss spacing. However, using flat girts on either side of the posts gives us an extra 3″ of insulation and also reduces thermal bridging in the assembly for the spaces between the posts (essential for getting the heat loss down for the building).

Is there any way to combine the two methods? For example, i was thinking of using intermittent single studs between the columns that are anchored to the floor to support the flat girts in between the posts.

Or are there any creative solutions that you have used in the past or can think of? Here are a few photos of my project for reference. If you have any questions feel free to contact me.

Thanks, KNOWING IN NEW YORK

DEAR KNOWING: Thank you for visiting our website, we hope you will continue to avail yourself of the free information available within it.

Post frame (pole building) construction will certainly be more affordable than any other permanent type of construction, and it does afford the ability to create some deep insulation cavities.

The challenge of flat girts on the outside of the columns is they (in most cases) will deflect more than what is allowed by the Codes. Read more about flat wall girt deflection here: https://www.hansenpolebuildings.com/blog/2012/03/girts/

Here is an idea which might meet with all of your needs…..between the wall columns, install either bookshelf style girts (https://www.hansenpolebuildings.com/blog/2011/09/commercial-girts-what-are-they/) or construct a vertical stud wall with the thickness of the wall matched to the size of the wall columns. With bookshelf style girts, make the girts the next size larger than the columns, and leave 1-1/2″ sticking outside of the column faces. In the stud wall scenario, place 2×4 “flat” girts on the face of the studs, across the columns, at 24 inches on center. Regardless of the route, use a high quality building wrap to cover the girts prior to application of either sheathing or siding.

I’d recommend the use of BIBs insulation: https://www.hansenpolebuildings.com/blog/2011/11/bibs/

On the inside – Use reflective insulation with adhesive pull strips as your vapor barrier, then apply drywall.

Good Luck and let me know how you come out – I appreciate the photos!

Mike the Pole Barn Guru

DEAR POLE BARN GURU: Greetings, are the “typical” roofs -as in your monitor style project 04-0328, considered “walkable” for once in a while fixes? Not planning on making it a habit –just good to know ADVENTURING IN ARIZONA

DEAR ADVENTURING: I’ve been asked this question more than a few times over the years, and have always wondered why it is anyone would actually want or need to be walking around on their roof. With steel roofing, unless it is installed improperly in the beginning, there should never be a “fix” to be made.

Shingled roofs are an entirely different story – as shingles are very susceptible to damage, especially from hail. For more reading on hail damage:

https://www.hansenpolebuildings.com/blog/2013/05/steel-roofing-5/

The answer to your posed question is – yes, the roofs can be walked on. Because steel roofing can be slippery, if you feel the desire to walk on the roof, please use care to step only where there is a screw – the head of the screw will give a traction point to help you stay on the roof. And be sure to use shoes with good soles on them.

Mike the Pole Barn Guru

DEAR POLE BARN GURU: Scissor trusses, or raised lower cord and false economy?

Some claim that the increased cost of the truss is offset by the reduction in side wall height. CHAFING IN CHAFFEE

DEAR CHAFING: For just a moment let’s assume the scissor trusses add no extra cost. A tall door is placed in the center of an endwall (after all – the concept of scissor trusses is most often to be able to get a taller door, into an eave height the door should not fit in). The door is opened and the VTT (very tall thing) is driven into the building. The then driver decides the VTT would be ideally parked off to one side, rather than right in the center of the building, where it cannot be easily gotten around.

A loud WHAP is heard, right before the roof caves in on top of the VTT, because the VTT has run into the bottom chord of the scissor trusses – which are lower closer to the sidewalls of the building.

In nearly every case I can imagine, it will be less expensive to have a taller sidewall and complete unobstructed use of the inside of the building, than to go with scissor trusses.

There are some cases where scissor trusses make sense – and none of them have anything to do with economy.

Planning upon finishing the ceiling and like the look of a vaulted ceiling? Scissor trusses make sense.

Your Planning Department has a restriction upon eave height (but not overall height) – scissor trusses again make sense.

The verdict – false economy.

Mike the Pole Barn Guru

DEAR POLE BARN GURU: Per square foot cost of steel pole with 6″ concrete floor and pitch roof with 14′ door. BONKERS IN BAY CITY

DEAR BONKERS: As the boss used to say, $3 a square foot, but you need to cover at least an acre. Have an 8’ eave with no walls, lots of interior columns and an uninsulated galvanized roof.

Pole buildings, just like any other form of construction, become more cost effective as the “footprint” of the building increases. Want to lower the cost per square foot? Enclose more square feet. Or reduce the eave height. Or go narrower and longer rather than wide but shorter. Or don’t put on any doors. Or take off the overhangs, wainscot or other features. Or….get the picture?

The quickest and best way to get an exact price on any pole building is to put in a request for a quote at: https://www.hansenpolebuildings.com/freequote.htm

And if you get a quote, don’t compare a 40’ wide by 24’ deep to someone else’s 60 x 80 by only using “per square feet” as your measure. Get a comparison of “apples to apples” – that’s the only way you will know exactly what you are paying for.

Mike the Pole Barn Guru

Dear Guru: Which Insulation Should I Use in My Metal Pole Building?

DEAR POLE BARN GURU:  I have a few questions that you might be able to easily answer.

I have a metal pole building wood framed. Most of it has the standard Condensation/insulation blanket in it however some of it got damaged by mice and had to be ripped out. We are now trying to finish that area of the building to use as an office, Heated but NO A/C.

To make this a little more complicated the room is already pre-framed out to add extra insulation, this framing is now blocking any good access to the beams and girts that are structural (I have pictures but don’t know how to attach).

When talking to insulation contractors I have gotten mixed and conflicting information, I am not sure how much they know about insulating metal buildings.

How to insulate?

1. Can I use Fiberglass batts then cover with a vapor barrier and sheetrock? (The wood framing would be in the fiberglass batts) If I can… do I leave space between the fiber glass and the metal or do I want the insulation to be in contact with the metal and fill the wall as much as possible? (One insulation guy said to PACK it as full as possible with NO air gaps)

2. If the Fiberglass will not work properly installed this way, (condensation problems?) would I want to use 2″ closed cell Spray foam? Would the spray foam cause any damage or issues with the metal siding?

3. Should I do this a totally different way than I have asked?

4. Is there any issue to adding Fiberglass bats insulation between the purlins, in effect creating a hot roof. KITSAP KELSEY

DEAR KELSEY: You’ve made some good progress getting everything stripped down to the point you are at.

 One wall at a time, I would remove the wall steel and install a quality housewrap. Make sure to leave enough to tightly cover around corners. You may be surprised at how quickly this can be done and the siding reinstalled. It is a good idea to use larger diameter/larger diameter screws to reattach.

 Rather than batt insulation, install BIBS insulation. It will completely fill any voids and give a higher R value than batts.

 Packing batt insulation in as tightly as possible would severely reduce the R value of the batts. Fiberglass batt insulation is effective only when not compressed – it is the dead air trapped within the fibers which gives the R value, not the fiberglass itself.

 Placing batts between the roof purlins is not a good idea. The Code requires insulation batts in vaulted ceilings to have continuous air flow (ventilation) above the batts. Even if say 3-1/2” insulation was placed between them, the dead air above the fiberglass would be trapped between the purlins, taking away any possible airflow (not to mention having to also have sufficient ventilation at the eaves and the ridge). It would also create an airspace trapped between two vapor barriers, the condensation control blanket insulation between the purlins and the roof steel, as well as the facing of the batts.

DEAR POLE BARN GURU: I am planning to build a pole barn. I want to build it on the side of a hill with one side built into the hill. I would like to build into the hill to a depth resulting with about a 5 ft earthbag wall with crusher run limestone in the bags. A french drain would be put on the outside with some crushed rock to relieve hydraulic pressure. I would like some ideas on how to interface the poles to the earthbag partial wall. Would buttresses be needed? I can cut some red oak lumber on my portable sawmill for the sill on top of the earthbags or do a concrete beam. If the poles are 6”, and are set in the center of the bag, how do I get the siding to shed water on the outside of the bags. I know I will need to put girts on the poles for siding but they typically aren’t more than 2x4s. Looking for ideas. EARTHBAG

DEAR EARTHBAG: Post frame buildings, are by their very nature probably the easiest building for an individual to construct on their own. My first thought is why take something so simple, and make it more difficult than it has to be? Not to mention the many additional costs you have outlined.

Rather than trying to incorporate the earthbags into the building itself, why not just build an independent retaining wall away from the building? This would eliminate so many potential issues and would make the pole building construction easy, as it should be.

Dear Pole Barn Guru: What Type of Insulation Should I Use?

Hansen Buildings new feature for each Monday is “Ask the Guru” where you can submit questions for Mike the Pole Barn Guru to answer on future Monday blogs.

Email the Guru at: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU:  I purchased one of your pole building kit packages late last summer, and have just finished constructing it. I was wondering if you had any recommendations on how I can best insulate it?                COOL IN MARYLAND

DEAR COOL: You and your Building Designer worked very well together to craft a new building for you which is ideally set up to be insulated.

You ordered the following features which will allow for the building to be easily insulated:
The ridge has a continuous vent,
The enclosed overhangs have vented soffits,
The roof trusses are designed to support the weight of ceiling framing, drywall and insulation,
Ceiling joists are in place every 24″ to support drywall,

Reflective radiant barriers are between the roof purlins and the roof steel to prevent condensation issues in the attic,

And your walls are framed with commercial girts every 24″, which creates both an insulation cavity, as well as allowing for a flat finished interior wall surface.

Most heat loss is up (as heat rises), so this is the most important area to tackle. We would recommend hanging 5/8″ drywall from the ceiling joists. You could then blow in as much fiberglass insulation as you desire into the attic space, the cost of insulating has as much to do with the installers having to make a trip and do the work, so paying for what may seem to be a few extra inches of insulation, is a bargain compared to having to add more at a later date.

For the walls, I always recommend BIBS. This is a netting stapled to the wall girts, with insulation blown behind it under high pressure.

For more information on the BIBS system: https://www.hansenpolebuildings.com/blog/2011/11/bibs/

As an alternative, you can also use R-19 batt insulation between the girts, which is less expensive because you can install it yourself.  But BIBS will be a far superior product, in my humble opinion.

DEAR POLE BARN GURU: I’m renovating a 60′ x 80′ Wicks Pole Barn and one of the things I want to do is put in a metal ceiling and insulate. The “barn” which is really a machine shed was built in the mid 1970’s and the trusses are in good shape, they are of a “A” design, arched up on the underside a few degrees.

Did the manufacturers use the same trusses whether or not the building was going to be finished off with a ceiling and insulation?

I don’t want to have the thing come down around my ears after putting all that time and money into it!                   COLD IN INDIANA

DEAR COLD: Typically, unless specifically ordered otherwise, pole building trusses are NOT designed to support the weight of anything other than their own weight, necessary bracing and minimal weight from wiring and lighting. Whilst it is possible the trusses could have been designed to support weights beyond these, it would not be safe to assume they can.

I’d recommend have a RDP (registered design professional – aka engineer) do a thorough investigation of the trusses and provide a sealed letter to confirm they are indeed adequate for your intentions, or if not, to design an engineered repair to upgrade them.

Yours is a case where an ounce of prevention, is more than worth the pound of cure.

How to Design a Climate Controlled Pole Building

When I first entered the post frame industry over three decades ago, most pole buildings were barns. Having a climate controlled building  (heating and cooling) was rarely a consideration.

Modern pole buildings, serve a plethora of purposes from homes to offices, retail space to churches and everything in between. HVAC (heating, ventilating and air condition) becomes an important consideration.

This blog is nowhere near an in depth guide to climate control, but intended to give the reader a starting point.

The first stop should be to check the recommended R-value calculator:

https://www.ornl.gov/cgi-bin/cgiwrap?user=roofs&script=ZipTable/ins_fact.pl

If starting with a concrete slab on grade, a layer of A2V insulation should be properly installed below the slab.

Walls should be framed with bookshelf style girts placed at 24 inches on center. Also referred to as commercial girts, they create an insulation cavity, which allows for fiberglass insulation batts to be installed horizontally between the wall girts. If steel siding is used, it could be beneficial to use a quality housewrap between the wall girts and the siding. With commercial girts, to properly size the insulation cavity, create a space equal to the depth of the pole, plus the 1-1/2″ outside of the posts where girts extend. This allows for drywall to be attached to the inside face of the wall girts, creating a smooth wall surface.

Another great option for wall insulation is BIBS – which provide a higher R value than batt insulation, as well as filling all of the voids.  If you are not familiar with BIBS, check out their website: https://www.bibs.com

As a sidebar, I have BIBS in my large three story (84’ x 60’) accessory  climate controlled building (yes, it’s a pole building).  The cost savings on our heating and air conditioning bills is testimony in and of itself for this great product.

Ceilings – use ceiling loaded trusses with ceiling joists 24″ o.c. Sheetrock can be attached to the underside of the ceiling joists and insulation can be blown in above.

Any time a dead attic space is created – the attic space MUST be ventilated. As long as 1/2 of the required ventilation area is in the upper 1/2 of the attic, the area of the attic vents must be 1/300th of the footprint area of the attic. Otherwise, 1/150th is required. The best way to get even attic airflow is to use enclosed vented overhangs in combination with a vented ridge.

As I said, this is a primer for how to ensure a climate controlled pole building.  Ask whoever is designing your new building for more assistance. I have far more concerns for folks wanting to over-design climate controlling their new pole barn, then “under”.  While I want you to be warm (or cool) and comfortable, I also want to be sure you are using the “Three R’s Rule” – selecting the right product, to do the right job, at the right price.

What is BIBS® Insulation?

I’ve personally used and experienced wonderful results with a product referred to by the trade name BIBS®.  You can read more about it on the internet:  www.bibs.com

I know I’m going to sound like a commercial talking about how great this stuff is, but I honestly have no affiliation with the company producing it. I just happen to have used BIBS® insulation in my most recently constructed building, and I love it.

What is it?  Simply, a shredded fiberglass material mixed with a light adhesive.  A fine netting is placed over the inside of the framing and insulation is blown into place.

Besides offering an “R” value of over 4 per inch, I was impressed when standing inside my building with the wind blowing 60 miles an hour outside.  Inside…it was completely quiet.  If I hadn’t been fighting the raging wind outside earlier in the day, I’d have never known the wind was blowing so hard.

And because BIBS® is blown in, there are no gaps. It eliminates voids, thus reducing heat loss.  Due to its density and the way it’s blown in under pressure to fill every space, there is no settling.  I can attest to this as I have some yet unfinished areas in the 3rd story area of my building, and over seven years later, there are still no gaps or evidence of settling!

When my wife and I considered insulation for our big storage building (60×84), with a loft for our new “living space” we checked out all types of insulation.  BIBS® insulation was less expensive than foam, and had some advantages due to the design of our new building.  Five years later, we‘d do it all over again. We are often surprised to wake up mornings finding it has rained and realize we didn’t even hear it, even with a steel roof.

BIBS® was blown into some very irregular spaces in our pole building. It has a gambrel roof style and custom designed windows, which have odd angles and spaces around them.  I know we’d never have filled those voids with any other type of insulation and had such a complete and tight “fit” with any other insulation.  Having the insulation tight around plumbing reduces the possibility of freezing pipes in the wintertime.  We have no drafty outlets…no drafty anything, due to BIBS®.

Probably the only “down” side to this product for you do-it-yourselfers is it is only installed by certified BIBS® installers.  However, to their credit they come in knowing exactly what they are doing, so having experienced installers cuts down on labor costs overall.  I know this is one “do-it-yourself” project I am happy to pass along (this and concrete!) to those “in the know”.  There are just some things you want and need to have done “right” and this is one of them.  After seven years, I am a happy camper with the results of choosing BIBS® for part of our insulation needs.  We have a phenomenally low heating and A/C bill, amazing sound control (quiet!), and maybe just the feeling of being “snug as a bug in a rug” …which is pretty nice considering winter is…coming!