Tag Archives: Ventilation

Hoop Shed Wall, Ventilation, and Pole Barn Footings

Today the Pole Barn Guru answers questions about adding a garage door wall to a hoop shed, ventilation with no sidewall overhangs, and how post frame buildings are “anchored” to the ground.

DEAR POLE BARN GURU: I would like to close the open 1/2 of the basketball court hoop shed with a pole building face.  I would like a large garage door in the center, fiberglass windows, and a door. Would you consider doing this project? JOHN in GILBERTSVILLE

DEAR JOHN: With no building behind to tie an endwall into, it would be structurally unrealistic and economically unaffordable to build what would essentially be a billboard in front of your hoop building. We would recommend tearing down the hoop building and replace it with a new post frame building which would be structurally sound and a permanent structure.


DEAR POLE BARN GURU: I have a 56×40 pole barn that I am working on lining and insulating. My question has to do with ventilation. There is no soffit. Does Hansen make an eave vent similar to their vinyl gable vents with the snap rings? They would need to be approx. 6 inches wide by 1 or 2 feet long. I would like to place something like that in between each truss (8ft centers) on the sidewall under the roof overhang. Or should I just do gable vents? We are installing a vented ridge cap. Thank You. DARRIN in ARKANSAW

DEAR DARRIN: Unless your trusses have raised heels deeper than whatever insulation thickness you intend to use plus vent height, adding vents at sidewall tops will not solve your ventilation issue. Ridge vents do not function well with gable vents as intakes, so I will make one of two suggestions –

If insulating at ceiling level, use gable vents only following this:

2015 IBC (International Building Code) ventilation requirements may be accessed here: https://codes.iccsafe.org/public/document/IBC2015/chapter-12-interior-environment please see 1203.2.

In areas closest to sidewalls, use closed cell spray foam insulation until you reach an area where full depth blown in fiberglass insulation can be used (20″ will provide recommended R-60 for your area).

Or – use no vents and closed cell spray foam underside of roofing and triangles of gable ends.


DEAR POLE BARN GURU: How is the plumbing in pole barn construction affected in an earthquake? I have heard that since the pole barn construction is not anchored down, it shifts during an earthquake causing all kinds of damage to the plumbing? CARLOS in SPRINGDALE

DEAR CARLOS: Pole barn (post frame) buildings are indeed anchored down – or least most should be. In our case engineers we utilize will specify a bottom collar of a minimum 18 inches diameter and 16 inches deep, at base of a 40 inch or deeper hole. Columns will be attached to a slab on grade, or restrained by an elevated wood floor, if over a crawl space. There should be no more damage to plumbing, due to an earthquake, for post frame construction, than there would be for any other form of construction.




Electrical Planning, Moisture Issues, and Ceiling Barriers

Today the Pole Barn Guru fields questions on electrical planning, moisture issues, and ceiling barriers.

DEAR POLE BARN GURU: Good Morning/Evening:     I currently have a 36′ wide x 48′ long with 12′ tall ceiling pole barn that I would like wire for lights and outlets.   I intend to run main power from the street pole to a meter base and into a internal breaker box.  I know you have/sell electrical planning layouts for the internal pole barn light/outlets and I would like to purchase a set for use as a general guide.  Can you tell me how I might purchase your pole barn electrical layouts, etc.??    Thanks for your help in advance.   Very Respectfully. BILL in AMHERST

DEAR BILL: Thank you very much for your inquiry. We do not involve ourselves in any sort of electrical. No electrical materials, no layouts, no plans. Try visiting the ProDesk of your local The Home Depot for assistance.


DEAR POLE BARN GURU: Hi I’m emailing because I’m having issues with moisture in my building it happens when it freezes and then thaws and it only drips from the pillars and I have moisture barrier inside can you please explain why that’s happening. ROBERT in CHEHALIS

DEAR ROBERT: We receive a handful emails with challenges such as yours every winter, from clients who recently had their buildings completed. It all goes back to where is moisture source?

If no concrete slab in your building, it is because ground outside of your building freezes before ground inside. When this occurs it is like pulling a cork from a bottle – all ground moisture from area surrounding building tries to escape through your building.

Have a fairly new slab on grade in your building? Moisture will be coming from it. As long as you have a well-sealed vapor barrier under your slab, you should only experience this issue for one winter. You can speed this process along by keeping large door(s) open on days when dew point stays lower than outside air temperatures (lower humidity, faster water will exit your slab).

If a well-sealed vapor barrier was not installed under your building’s slab, then slab surface should be sealed (once it dries out).


DEAR POLE BARN GURU: Hello. I plan to use foil backed foam sheets for my ceiling in my 28 x 34 Pole Building / garage. Reading your article, you would NOT put up a plastic barrier to control heat loss before hanging the Foam board? 4 / 12 pitch. Recommendation for hardware to secure sheets to trusses?
Thank you DAN in BUTLER

DEAR DAN: A plastic barrier would not make any difference in controlling heat loss, as it has no insulating value. Your foam board, if installed properly with joints sealed, will act as a vapor barrier. I’d glue it to truss bottoms to eliminate transfer of heat through nails or screws. Make sure to adequately ventilate dead attic space you are creating and a provision for preventing warm moist air from contacting roof steel underside exists.



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.

A Steel Ceiling, Wall Finishes, and Condensation

Today Mike addresses questions about steel ceilings, options for wall finishes, and condensation in added space.

DEAR POLE BARN GURU: I have a 40ft wide x 60ft long x 12ft high pole barn. The trusses are 4ft on center. I want to put a steel ceiling up and wanted to know the best size piece to use when putting it up. 8, 10, or 12. MICHAEL in TABERNACLE

DEAR MICHAEL: Before consider this move confirm your trusses are designed to support added ceiling weight across bottom chords. Also, make certain to adequately ventilate dead attic space you will be creating (read about adequate ventilation here: https://www.hansenpolebuildings.com/2018/03/adequate-eave-ridge-ventilation/).

Having satisfied above, if you intend to merely attach steel panels to truss undersides and run panels lengthwise, I’d go with 28’ and 32’ long pieces to minimize splices. If framing has been placed between trusses to support steel running across building, go with full length panels and have no splices.


We have a new pole building and are looking at options for finishing the interior walls. The building has been well insulated and will have a heater and AC unit. Besides drywall, what other options are available? LISA in MIDDLETOWN

Finished Pole Building InteriorDEAR LISA: Gypsum wallboard (sheetrock) will certain be most common as well as most popular option. If you go with 5/8″ thick Type X, it will also be fire rated. You can use any material for covering walls one would find in any type of building – however most of them are still installed over sheetrock. If for a shop building, 7/16″ OSB proves to be quite popular. Some people like steel liner panels, however I find them difficult to attach things like shelves and cabinets to and they get dented.


DEAR POLE BARN GURU: Greetings.  I have a 20-year old 40×25 post and beam barn, 2 story, shiplap siding, with metal roof and concrete floor.  Last summer I walled off a 11.5×25 area for a workshop (10ft ceiling) and noticed a lot of condensation this past spring (after pouring the concrete floor last fall). The workshop is used sporadically from spring through fall. I would appreciate your advice on how to address condensation issue and any recommendations for insulation.  Thanks for your time. RALPH

DEAR RALPH: Your increase in condensation most likely comes from moisture leaving concrete as floor cures. If you placed a good vapor barrier properly under slab, it should eliminate this as a source of moisture for condensation. If you did not, then you will want to seal slab with a high quality sealant. If condensation issues continue, it may be necessary to add a powered exhaust vent. Click here for further reading about insulation for different post frame uses: http://www.hansenpolebuildings.com/2018/06/pole-barn-insulation-part-ii/






Will My Post Frame Building Support a Ceiling?

Will My Post Frame Building Support a Ceiling?

One of my frequently received questions – wanting to add a ceiling into a post frame building and wondering if the building will support the added weight. Other frequent questions include condensation issues and ventilation, so this reader has hit upon a trifecta.

Reader BRYAN in SWANTON writes:

“I am having some condensation issues. And I was curious about insulating the building. Also wanted to ask if my building is able to have a ceiling installed. Thanks for the fast reply.”



By any chance have you recently poured a concrete slab-on-grade inside of your building? If so, until concrete fully cures, it will expel a great deal of moisture inside of your building. Solution – open your doors to allow moisture to escape and keep them open until condensation issues no longer exist. Read more here: https://www.hansenpolebuildings.com/2018/01/condensation-roof-steel/.


If you poured a slab without a well-sealed vapor barrier underneath, it will contribute to excessive moisture challenges. If no vapor barrier, top of slab should be sealed: https://www.hansenpolebuildings.com/2018/11/siloxa-tek-8505-concrete-sealant/


Your new post frame building and its trusses were not ordered to be able to support the added weight of a ceiling. It may be possible to upgrade your trusses with an engineered repair to be able to carry a bottom chord dead load of five psf (pounds per square foot) or more. Plan upon an investment of $295 (plus sales tax if applicable), even if a truss repair cannot be designed. Contact Justine at justine@hansenpolebuildings.com if you are interested in going this route.

If you are able to get a repair to install a ceiling, this newly enclosed attic area will need to be adequately ventilated. This may be a possible solution: https://www.hansenpolebuildings.com/2018/07/my-pole-barn-needs-ventilation/

In order to insulate, best solution (although costly) may be to use closed cell spray foam insulation. If you purchase an insulation kit for your overhead door, you will need to change out door springs in order to handle the added weight.



Whiskey Tango Foxtrot! Is It Ventilation?

Whiskey Tango Foxtrot! Is it Ventilation?

I really enjoy good food. In order to continue doing so and avoid weighing significantly more than I should, I do a treadmill run nearly every morning. To keep from expiring from utter boredom of exercise, I have wall mounted my flat screen LED television within easy viewing distance. With subscriptions to Amazon Prime and Netflix, I have yet to run out of movies and series to view. Most movie selections are either fairly old, or were box office challenged. One of these movies was 2016’s Tina Fay starring in Whiskey Tango Foxtrot, with a budget of $35 million and a box office take of $18.3 million.

Well, this article isn’t about how Tina Fey carried this movie. To be precise, it’s a movie title conveying my expression upon doing some recent reading.

Back in 2016 I had penned an article (https://www.hansenpolebuildings.com/2015/06/overhang/) mentioning a specific pole building company by name. A representative of this company recently contacted Hansen Pole Buildings’ owner Eric to let him know they did not appreciate being named. I was even kind enough to have included a live link to their website in my article, providing them with free press.

While editing, I happened to peruse their website. When a Whiskey Tango Foxtrot moment hit me…..

Under ‘Building Features’ I found this gem, “(Our standard roof to eave or gable design creates a fully ventilated structure making boxed overhangs an option, not a necessity)”.

I had to read it several times to fully get my head around what I thought I had read.

In order for this statement to be true, roof steel high ribs would need to remain unobstructed – allowing a free flow of intake air. This could possibly pose a challenge if one desires to keep small flying critters from entering a dead attic space.

In my humble opinion, this attempted ventilation intake ranges from laughable to totally ridiculous. However, I have found, nearly anything can be spun to sound like a benefit. What should be happening between roof steel and eave strut – placement of an Inside Closure (https://www.hansenpolebuildings.com/2015/12/the-lowly-inside-closure/), to seal these openings.

IBC (International Building Code) 2015 Edition tends to agree with me.

“1203.2.1 Openings into attic.

Exterior openings into the attic space of any building intended for human occupancy shall be protected to prevent the entry of birds, squirrels, rodents, snakes and other similar creatures. Openings for ventilation having a least dimension of not less than 1/16 inch and not more than ¼ inch shall be permitted. Openings for ventilation having a least dimension larger than ¼ inch shall be provided with corrosion-resistant wire cloth screening, hardware cloth, perforated vinyl or similar material width openings having a least dimension of not less than 1/16 inch and not more than ¼ inch.”

Thinking about a post frame building other than from Hansen Pole Buildings? Before possibly throwing away your hard earned cash, give us a call – if we feel someone else’s building has a better value than ours, we will be first ones to tell you to invest in it.


Mold in a Post Frame Building Attic

Hansen Pole Buildings’ client BRENT in WASHOUGAL writes: “We have your 40×80 pole barn built sept. 2014, and it’s having problems with mold forming over the purlins. I’m wanting to know my options to prevent a future problem.


Mike the Pole Barn Guru responds:

First – 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.

The most common causes of attic mold are leaking roofs, inadequate ventilation and too much humidity in the building itself. If your concrete floor has a vapor barrier underneath it and/or is well sealed, you are probably not drawing in excess moisture from underneath the building – so we will look at the first two.

Mold showing along the tops of the roof purlins and not on the trusses, as well as the streaks down the sides of the purlins leads us to believe you may have screws which were inadequately placed. Screws which are not properly seated so as to compress the rubber washer, will leak. Screws which are driven in at an angle will also cause leaks. The roof should be investigated screw-by-screw to make sure all screws are properly driven. Water leaking around a screw shaft will eventually cause decay of the wood around the shank, so if screws cannot be tightened they should be replaced by a larger diameter and longer screw – in your case a #14 diameter by two inch long part.

Ventilation – in an ideal word your building would have had enclosed vented eave overhangs of 18 inches or greater on both sidewalls for an air intake, as well as a vented ridge to provide an exhaust point. This ventilation system provides for even airflow from eave to ridge throughout the entire attic area. Gable vents can be used to meet Code requirements for ventilation, however the reality is they are not very effective in providing ventilation other than near each end of the building’s attic. The Code requirement would be for 1/300th of the footprint area of the attic to be provided for as net free area of venting, as long as at least 50% of the venting is in the top half of the enclosed attic space. With a 40′ x 80′ building, you have 3200 square feet of footprint, which would require at least 10.67 square feet (or 1536 square inches) of net free ventilating area. To give an example a Mid America (www.midamericacomponents.com) Classic Rectangular vinyl vent 20 inch by 30 inch provides 297 square inches of net free ventilation area, so it would take three of these in each endwall just to meet the requirements of the Code!

There also is a difference between meeting Code requirements and what actually works in a real life situation.

Since you cannot increase the amount of venting in your soffits (as you have none), you’ll need help from power vent fans to exchange the moist air in your attic for dryer, outside air. Attic ventilation fans would help move the moist air out of the attic without giving it time to find a home on the purlins and trusses.

Attic vent fans can be hard-wired and equipped with a thermostat and/or humidity sensor so they automatically cut on at a preset moisture level or temperature. You could also install solar-powered attic vent fans, though it has been found most solar models aren’t powerful enough to be very effective.

To determine what size power vent fan(s) you need for your attic, you first need to know the size of your attic in square feet.

Attic Size

To determine the size of your attic, multiply the width by the length of the attic floor in feet. In your case 40′ wide x 80′ long = 3200 square feet of attic space.

Vent Fan Size

Next, multiply the square feet of attic space by 0.7 to get the minimum number of cubic feet of air per minute the fan should be rated to move. 3200 sft x 0.7 = 2240 CFM minimum fan rating.

Add an additional 20% (CFM x 1.20) if you have a steep roof, and 15% (CFM x 1.15) for a dark roof. Attic vent fans are commonly rated from 800 to 1,600 CFM, making one fan suitable for attics of up to around 1160 square feet, even with a steep, dark colored roof.

Vent Fan Location

Install gable mounted fans on the gable vent at end of the building facing away from the prevailing winds.

Intake Air Vents

It’s also important to have plenty of soffit or gable vents for the fan to draw air into the attic. To find out if you have enough vent space, divide the cubic feet of air per minute the fan(s) is rated for by 300 to come up with the minimum number of square feet of intake vent space needed for that size fan. 2240 CFM ÷ 300 = 7.47 sq. ft. intake vent area

If you prefer the answer in square inches rather than square feet, multiply the answer by 144 and round to the nearest inch (7.47 x 144 = 1075.2 sq. in. vent area).



How Not to do a Post Frame Sheer Wall

How Not to Do a Post Frame Shear Wall

Reader DAVID in MIDDLETON writes:

“Hi we are currently building a 40/72 pole barn. We are wrapping the bottom 4 feet in OSB for sheer strength along with sheeting the roof with osb. We want to insulate the walls and put a drop ceiling in the pole barn to fully insulate it later this year. What do we need to do now for ventilation while we are building it to make sure we don’t have condensation issues later.”

Whilst friend David is writing about one issue, he is throwing out a bone as to why self-engineered post frame buildings are not always the best route to go. David is well intentioned, however his design solution would result in added expense without added benefits.

Always (may I repeat Always) construct only post frame (pole) buildings which are designed by a RDP (Registered Design Professional – engineer or architect) specifically for your building upon your site. You will always get piece of mind and usually the RDP will save you more money than what you invested for their design work.  

Here is my response to David:

Before we get to discussing your question, a few words about your design.

Wrapping the bottom four feet in OSB is going to do little or nothing to improve wind sheer resistance. In order to be effective as a sheer wall, the OSB needs to run from the splash board up to either the eave girt on the sidewall or the bottom chord of the truss on the endwall. All panel edges need to be blocked with 2x material. The shear panels should be no less than a 1:4 ratio (one foot of shear panel width per four feet of height) and ideally 1:2. On the roof, make sure to use at least 30# felt between the OSB and steel roofing and locate the roof screws so as they go into the underlying purlins, not merely into OSB.

Back to the question at hand…..

Your building should have vented soffits, of at least 18 inches in width to provide an adequate air intake. Trusses should be fabricated with raised heels – ideally two inches higher than the thickness of the attic insulation. Take care not to block the airflow from the soffit with the attic insulation. Vent the ridge.

Pour the slab on grade only over a well sealed vapor barrier, otherwise excess moisture will enter the building from the ground beneath the building. Also, the slab will need to be sealed – not as good as the vapor barrier route, but it is better than doing nothing.

Completely fill the wall cavity with insulation. Unfaced batt insulation can be used, however BIBs will be a fair superior design solution. Read more about BIBs here: https://www.hansenpolebuildings.com/2011/11/bibs/.

Either choice of wall insulation requires a clear visqueen vapor barrier on the inside. Make certain to seal any seams, rips or tears. There should not be a vapor barrier between the ceiling framing and ceiling materials.



Considering a Pole Barn, Roof Loads, and Proper Ventilation

DEAR POLE BARN GURU: Good morning.

I am considering building a pole barn on our land in northwest Georgia and wanted to know the following:

1) On your website, you list links for residential, agricultural, and commercial buildings.  What is the difference between a those three types of buildings?  Are they different because of design or do they each involve different construction materials?  Do the commercial buildings use a lower gauge (thicker) sheet of metal for siding than a residential building?

2) Do you have any product comparison documentation between your kits and the other pole barn kits on the market (DIY, Menards, etc.)?  Interested specifically in design, material, and construction comparisons.

3) Would your pole barn kits be able to accommodate a chimney/stove pipe if I wanted to use a wood burning stove for heat?


About Hansen BuildingsDEAR CHRIS: The differences for residential, agricultural and commercial buildings shown on our website are for the convenience of those who are looking for a particular end use, it keeps from having to browse through a plethora of photos of buildings which may not be what one is looking for. The construction materials and methods used are going to be individually tailored to the ultimate end needs of each client, as well as the climactic conditions of a particular site.

Our goal is to custom design for you a building which best meets your wants, needs and budget. We are so confident in our ability to provide the best possible value for your post frame building investment, once this is done, we would happily shop this building for you with any other provider or providers you so desire. How easy is this?

(BTW – Menards might be a bit geographically challenging as their nearest location to you is in Owensboro, KY)

Actually any post frame building (not just a Hansen Pole Building) can accommodate a chimney/stove pipe with the use of a Dektite® (read more here: https://www.hansenpolebuildings.com/2012/09/dektite/).


DEAR POLE BARN GURU: I have a 30 year old pole barn that is 30’ x 40’ x 9’ tall. It has a metal roof, trusses are 4’ on center. Can I tear off the metal on the roof and put down OSB and shingles? JIM in LAWTON

DEAR JIM: Chances are excellent your existing roof system is not designed to support the weight of OSB and shingles, as most pole barn (post frame) trusses are designed for a dead load of only 3 to 5 psf (pounds per square foot) which includes the weight of the trusses themselves plus the roof purlins. Steel roofing weighs in at under one pound per square foot. 7/16″ OSB comes in at roughly 1.5 psf, 15# felt and shingles 2.5 psf making the weight combination more than four times greater than the steel.

The big question is – why? Even “lifetime” shingles will usually last only about 15 years and you know the steel roofing you have had made it twice as long. Steel is far more impervious to weather (especially hail) and readily sheds snow, unlike shingles. For my money, if I had to re-roof I would invest in steel roofing with a high quality paint system like Kynar. Read more about Kynar here: https://www.hansenpolebuildings.com/2014/05/kynar/.


DEAR POLE BARN GURU: I have a pole building with all metal sheeting. The interior walls are framed and insulated R13 batt. The ceiling is insulated with 1/2 foam a 3/4″ air gap then R19 on top. The underside of the roof is not insulated. I have eave ridge vent. Building is heated in winter. Can I exhaust fumes (paint,lawnmower,etc.) into the attic space and let it vent out the ridge or will I be causing a condensation problem? I will use a standard box fan to blow exhaust into the attic space. I’m also hoping to do this to help melt snow off the roof.

crash-test-dummy-symbolDEAR RICH: I’ve seriously struggled with your question for several weeks now. It lead me to spend hours researching the International Mechanical Code (I am proficient in the IRC and IBC, but not the IMC), looking for backup as to your scenario. In the end it all comes down to this – WHY would you want to dump toxic fumes and their waste into your attic? At some point this has got to be just plain unhealthy.

Whether you do or do not blow exhausts into your attic, your building has the strong potential for a condensation problem because there is no thermal break below the roof steel. You should look at having closed cell spray foam installed on the underside of the roof steel.

As to the heat from the exhaust helping to melt snow off the roof – do not count on it, by the time it gets into your attic, the heat generated will be minimal at best.

Turf Sweating, A Post Frame Addition, and A Grow House

DEAR POLE BARN GURU: Hello, I am from Webster SD and I built a pole barn and insulated it.  I then put turf above gravel floor and use it for a indoor baseball practice facility.  It can be heated as we have heaters in there.  We have a huge problem and was wondering if you could help us solve it.  I went in there today and the humidity was 85%.  Under the turf is wet.  What is causing this and how do we solve it?  We have bats in there that are showing early signs of rust and it has been closed up for about a month.  Thanks, CHAD in WEBSTER

DEAR CHAD: The water is coming from the ground, and even makes its way up through concrete. You will need to remove the turf and then install a high quality sealed vapor barrier which is resistant to punctures or tears beneath it. In the research I have done, it appears the folks at Americover (www.americover.com) can probably make the best recommendations as to the product which will best fit your needs and budget.

Depending upon how you have insulated the building, it may also be necessary to add ventilation in order to remove excess humidity from the air.

DEAR POLE BARN GURU: Can a pole barn be mounted to a house that has a cinder block foundation? RAY in BROCKPORT

DEAR RAY: If the question is can a pole barn (post frame building) be mounted to a block foundation, as long as the foundation is adequate to carry the imposed loads, certainly. Brackets are made to either pour into a foundation, or be retrofitted to one.

If you want to attach a post frame building to a house with a cinder block foundation, the post frame building would not structurally rely upon the block. Instead, it would typically be a free standing structure abutted to the existing building and foundation.



DEAR POLE BARN GURU: Is a 28×24 pole barn with 8 foot ceiling height large enough to start a grow room? ELIZABETH in DUNDEE

DEAR ELIZABETH: It will depend upon how many plants you intend to grow. A mature plant requires four square feet of area and you need to have space to walk alongside. The eight foot high ceiling might be a bit tight as well, as some plants have the capability to grow to be as tall as a house. My best recommendation is to err on the side of caution and construct the largest footprint building which you can economically justify and which will fit within the available space.



Premature Roller Wear, Proper Insulation, & Venting!

DEAR POLE BARN GURU: My Plyco rollers are wearing prematurely since I added liner to my doors. Can I put a 3rd roller in the center of each leaf to spread out the additional load? BRAD in EL DORADO

DEAR BRAD: If these are round Plyco trolleys, your door must be very heavy. I say this because I have never heard of one failing and we have thousands of sliding door in use by our clients. With this said, placing another one in the middle will probably result in the door sliding unevenly due to the slightly larger (due to no wear) new trolley in the center. Plyco does have what is referred to as a “double truck” trolley. These will replace your existing trolleys and each has two sets of wheel pairs. If you have a heavy sliding door, these are probably going to be your solution.



DEAR POLE BARN GURU: Can I use post frame insulation on the ceiling of my home. It is an add-on used as a day room. OVERTON in NATCHEZ

DEAR OVERTON: Could or should? Not the same question. You should be blowing at least R-45 of cellulose or fiberglass into a properly vented insulation cavity. If you do not have adequate thickness at the top of the walls, Add high R insulation boards as baffles so at least 2” of clear airflow comes through from the eaves. Then have closed cell spray foam insulation added until the R-45 blown in can reach full depth. Generally this should be about four feet from the walls in standard residential stick frame construction.



DEAR POLE BARN GURU: My question involves venting of the attic space. If the eaves are closed off, will the ridges in the roof metal not work as air channels to allow outside air to enter the attic space in the same manner as soffit vents? The plan would be to install a ceiling, blow in insulation and install ridge vents in the roof. MIKE in INDIANAPOLIS

DEAR MIKE: The ridges of the steel will not provide adequate airflow. Plus, they should be sealed off with inside closure strips to prevent flying critters from entering your building. If you do not vent the ridge, you can meet the ventilation requirements with gable vents. Read more on attic insulation for post frame buildings here: https://www.hansenpolebuildings.com/2014/02/pole-building-ventilation/.

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!!!


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

Turn a Horse Barn into a Home?

Re-purposing buildings is a popular American past time, as evidenced by the proliferation of big box lumber stores across the country. Here is a story about a new owner of an existing Hansen Pole Buildings’ horse barn, who is contemplating it becoming a home.

Tim writes:

“Hello, I just purchased a property that has a Hansen Pole barn that is new on it and I am wanting to convert to home any ideas and /or plans , I have attached a photo of barn  center section is 48×28 x14 and the 2 side sections are 48x12x10”.

Drum roll please:

You emailed me because you know and trust I am the expert and will not lead you astray. Or, this was the email address you happened to find, either one of which is totally fine.

In order to give you definitive answers I would need to know who the original purchaser of the building was, so we can pull up the plans and specifications for it, if they are available.

In the meantime, I will hope to give you my best guess answers. The existing building is most probably designed under Risk Category I of the International Building Code (being as it is used as a horse barn) which is for buildings of low risk to injure someone in the event of a catastrophic event. These would be non-residential structures. A residence is a Risk Category II structure – which has more stringent requirements for wind, snow and seismic events.

The real issues are most likely to come in designing to gypsum wallboard (sheetrock aka drywall) the walls and ceiling.

On the walls, the deflection criteria for walls which support drywall is much greater than a wall with only steel on the exterior. This can affect the size(s) of the columns and they may have to be added onto in order to provide adequate stiffness. It is likely you will use bookshelf girts on the walls to create an insulation cavity. If so, and they are properly sized, they should be stiff enough to support drywall.

The trusses, rafters and roof purlins are not designed to support the weight of a ceiling. This will require an engineered truss repair, as well as probably upgrades to the rafters on each side (addition of more members). If you are planning on attaching sheetrock to the underside of the roof purlins, more purlins will need to be added to reduce deflection – and the only real way to insulate between the purlins on the sheds is to use closed cell spray foam, which is not an inexpensive proposition.

Ventilation is going to pose an issue (which is why the closed cell insulation is the solve for the sheds). In the main portion of the building, if a dead attic space is created, it must be ventilated. I cannot determine from your photo if the building has enclosed overhangs or not. If they are enclosed and the ridge is vented, you are in luck. If not, then gable vents are the alternative and would need to be added.

My best recommendation – leave the barn and design a post frame home which truly fits your needs and lifestyle, rather than trying to fit what you want inside a preexisting box which requires a boatload of work to upgrade.

Shipped International, Post Protection, and EmSeal!

DEAR POLE BARN GURU: Can the kit be shipped international, like Philippines? ERIC in SUSANVILLE

DEAR ERIC: Post frame building kit packages can be shipped anywhere on the planet. In most cases, the components are delivered to the docks – in your case most likely the Port of Tacoma or Seattle, where it is reloaded into a container. As containers have a maximum exterior length of 40 feet, it will limit the length of any prefabricated wood roof trusses, unless they are designed to be built in halves and field connected.

Many countries will require the lumber to be treated with a fungicide in order to prevent possible contamination of their own forest resources.


The furthest I have personally shipped to has been Saipan.


DEAR POLE BARN GURU: I really like the idea of post frame construction for residential, not because it is cheaper but because I believe it is stronger. Maybe I should qualify that by saying it is stronger laterally (horizontally) but probably not vertically. What I envision as post frame is having posts made of pressure treated lumber like 6×6, 8×8 etc set deep in the ground in concrete, and these posts would extend to the top of the wall or where the roof begins.

My question is do you know of methods of treating the wood so that it does not rot so quickly? I was thinking that if one were to coat the wood in epoxy resin that would help greatly, but I don’t know. Or could you not encase it in some kind of liquid plastic that once dried you would stick the post in the ground. Thanks. JACK in COBB

DEAR JACK: Post frame buildings are actually incredibly strong in the vertical (compressive) direction as properly braced timbers can withstand a very large downward force. Post frame buildings will be more economical than any other permanent building system, as well as affording greater flexibility for architectural design.

Properly pressure preservative treated lumber will outlive you, me and probably our grandchildren. If I did not believe so, I would not have invested the money in owning three of them myself, including the 8000 square foot finished building we live in. If you are yet concerned about longevity, there are currently available commercial products which will isolate the columns from the surrounding encasement (https://www.hansenpolebuildings.com/2012/04/plasti-sleeves/).


DEAR POLE BARN GURU: Hi Mike, I recently found this blog and man is it helpful. I have been remodeling a 1977 24×40 pole building. Never had one before and I’m learning as I go… hoping I can build a new one later in my life I’m only 29. I completely replaced the roof/trusses etc. and installed bubble insulation under steel for condensation. No soffit only Ridge vent. I want to seal up my gables up to peak. How should I do this? Solid closure strips? Vented closure strips? Or Emseal AST? Thanks for your help and hopefully I can order a new building from you in the future. ZACH in BLACK CREEK

DEAR ZACH: Thank you very much for your kind words! I will guess your building has no endwall overhangs, if this is the case the best way to seal up those endwalls is to use Emseal AST (https://www.hansenpolebuildings.com/2016/03/emseal-self-expanding-sealant-tape-closures/) between the rake trims and the endwall steel.


If you have endwall overhangs, you should be able to use spray foam in a can (such as Great Stuff or Tite Foam) from inside of the building to spray up the high ribs of the endwall steel.


Blog Entries Lead to Post Depth Question!

DEAR POLE BARN GURU: Good morning.

I have been reading the various blog entries for several days, regarding pole barn construction.  I have been in contact with your design professional, but I a question that I thought might be a question that could possibly benefit others with a similar situation.

I am in the process of planning a 40X60 building for a shop for the business I have.  My planned (and only available) location has about 5′ of fall on the lot which would be on the 60′ side wall of the building.  I have built up a 50 X 70 pad.  This has been built up and compacted with red “clay” a term we use around here, referring to the material we call “fill” around here, generally used for the purpose of building up a building pad.  My original thoughts were to place a 6″ thick monolithic concrete pad with a footer, (I intend to run forklifts on it.) and erect a steel building kit.

Since the dirt pad was completed, I have since stumbled onto your site, and am looking at a pole building.  So, my question relates to setting poles.  How do you handle setting poles when half of the building will be over the top of built up soil base?  I know it can be done, and I am not concerned overly much with adequacy of the soil compaction, which at this point, it has been sitting for about 7 or 8 months since it was compacted, but it has not been tested for compaction.

But having never done this before, since I am not 100% sure, and have yet to dig holes, (but I do want to start later this spring) I wanted to know your thoughts before I proceed.


DEAR WESSLEY: And a fine good morning to you!

I believe you are going to find a post frame (pole) building to be a much more viable option for your new structure than all steel and this is why….

Although your fill has sat for 7-8 months, there is yet a chance of additional settling. Clay is also a very unstable soil to place footings upon – so if your consideration was to support a monolithic pad with a footing around the perimeter, unless the footing was at the depth of the undisturbed underlying soil there is a high degree of probability the building would settle or shift – leaving you an unhappy new building owner.

With your pole building – the columns which will be placed in the fill area should be ordered long enough so the base of the column (actually the concrete below the base of the column) will rest upon virgin soil. This will require some holes to be as deep as five feet, however most skid loader mounted augers will get this kind of depth. The columns placed in this manner should minimize the probability of issues from settling and give you a resulting structure which can be happily used for several generations.

DEAR POLE BARN GURU: I can build a 28×36 pole building with 12′ eaves on my lot. I would like double trusses spaced 12′ so I can have 3 bays. What would be the difference in truss design for one designed for roof load only compared to one that can also support a ceiling. Thank you. JIM in SALEM

DEAR JIM: At the bare basics – the trusses will have one or more of the following: higher grades of lumber used for top and or bottom chords; large lumber for top and or bottom chords; more internal truss webs; larger pressed steel connector plates.

Now some recommendations – when you have a ceiling, ventilation is required. The best way to do it is to have enclosed vented overhangs and a vented ridge. This gives both an air intake as well as an exhaust and gives smooth airflow throughout the entire enclosed attic space. If you are planning upon insulating the ceiling, raised heel trusses are the way to go (read more on the hows and whys of raised heel trusses here: https://www.hansenpolebuildings.com/2012/07/raised-heel-trusses/).

You get one opportunity to do your new building right or wrong, I’d sure like to see it done right!

DEAR POLE BARN GURU: I bought a house with an existing 38×26 pole barn. The barn has metal roof placed over 3/4″ rigid foam (ISO) screwed to the purlins (2X4 on edge). I can’t tell what the facing material is on the ISO, but its white and doesn’t seem like paper. There is noticeable water staining on the rigid foam which I believe is due to condensation. There is a vent ridge on the barn. The metal roof is a PBR profile. For the winter I would like to insulate the cathedral ceiling better (I don’t want to drop a ceiling as I have storage shelving that prevents this). What is the best option (besides spray foam). I was considering kraft faced batts stapled to the 24″ OC purlins. I could do an R13 since the purlins are 2X4s, but also considered an R19 and let the batts bulge out a bit as I’m not going to sheath it. I would have the ridge foam to butt up against which should allow ventilation on the opposite side still (adjacent to metal roof). What do you recommend? I have wood stove for heating in the winter time and use it to take the chill off when I work out there (ie not on all the time). PATRICK in INDIANAPOLIS

DEAR PATRICK: I am going to give you the answer you probably don’t want to hear…..the water staining is most probably due to roof leaks, rather than condensation. This happens when screws are placed through foam board, which causes the screw shanks to deform, slots to form beneath the screw heads and when the deformations or slots get large enough – it leaks. The best solution for the problem is to remove the roof panels, take out the insulation boards and throw them away, then reinstall the roof panels using 1-1/2 inch long screws with a larger diameter than what was previously used.

Placing any sort of batt insulation under the foam as it currently exists is just going to get you wet insulation. Trying to use R-19 insulation batts in a 3-1/2 inch cavity will net you R-13 as the insulation is only as effective as its fully expanded thickness.

Once you have removed the foam boards the solution seriously is to spray foam it. Code requires airflow from eave to ridge over the batt insulation, which is going to involve more work and cost than the foam – it would take two layers of 2×4 laid flat on top of the existing purlins, one set running up the roof and another set going the same direction as the purlins, to screw into. This will mess up any trims on the perimeter of the roof, resulting in purchasing larger coverage trims.

The original building owner’s lack of planning for future uses of the building have now become your expensive nightmare.

6 Cool Ways to Heat Your Pole Building & Barn

When winter arrives, pole building owners will need more than a tiny space heater and a quilt to keep themselves warm. Sitting on the couch reading a book in thermal pants, a heavy jacket, and snow boots isn’t the most comfortable way to spend the cold months, so we’d like to suggest a few heating options for your pole barn.

Electric Floor
Electric floors radiate heat from underneath tiles, laminate, carpet, or engineered flooring. You can install bare wiring or opt for pre-wired mats that simplify the process. Mats are likely to cost more to install, but both systems use only a minimal amount of electricity.

Radiant Ceiling
Radiant ceiling tiles are long tiles on the ceiling, usually placed in increments, that generate and radiate heat. They are useful for targeting heat only in certain areas, such as in a living area above the couch or a bathroom next to the shower.

Radiant ceiling tiles, unlike electric floors, sit outside of the ceiling, not the inside. Some models are designed for painting and most will accept add-ons such as exhaust fans and lights.

Cove Heater

Cove heaters are silent-operating radiant panels mounted near the ceiling. They are a great option for heating safely with kids or keeping your heating equipment out of sight. Pole barn owners opt for these when baseboard heaters are difficult to install because of safety hazards or obstructive furniture.

Duct Fan
If you have a central heating system, you can add a simple fan to your ducts to increase the flow of warm air throughout your pole barn. Since there is so much empty space inside pole buildings, duct booster fans can help spread your heat evenly and might even help you save on your electric bill.

Mount your fan near the outlet end of a heating duct. The pressure switch will sense air pressure from the forced air coming out of the furnace and switch the fan on when it needs to be on. Higher quality fans emit less noise, but prices can range quite a bit.

Room-to-Room Ventilation
If your pole building has quite a few separate rooms to heat, you can circumvent your insulation and install a room-to-room ventilation system. These systems, installed as ducts in the wall, take warm air from room A through a low vent in the wall and push it up through a high vent in room B. Ventilators help draw the air through space between studs and distribute the warm air evenly into the adjoining room.

Ceiling Fan Heater

Ceiling fan heaters distribute air in the same way an ordinary fan does, but a heating element also provides the spinning blades with additional warm air to push throughout the room. Pole barn owners can turn the heating element off during the spring and summer to allow the ceiling fan to function like a normal fan.

Final Words: Stay Safe
You may have to deal with some unusual problems when battling winter weather. Remember the following:

  • Condensation Build-Up – Burning propane, methane, or kerosene can produce moisture in the air that, when it drops below the dew point, will cause water to condense inside your pole barn. Rapid changes in temperature can also pull moisture from the air and turn it to liquid. Use desiccators and dehumidifiers to control moisture in your pole building before it causes damage.
  • Ventilation – It’s tempting to trap all the warm air inside your pole building, but you have to let the air flow freely from inside to out and vice-versa. Proper ventilation keeps air fresh, oxygen-rich, and helps prevent heating-related disasters.

All heating creates some kind of fire hazard in your home. Be sure to operate all equipment according to instructions and prepare your pole barn heating system to resist fire by keeping it clean and having it inspected regularly.

Dear Guru: Can I Add to My Pole Barn in the Future?

DEAR POLE BARN GURU: I’m very interested in doing business with you, I just have a few questions. I originally asked for a quote of a pole barn of 200×50 I believe it was, my question is, can your buildings be added on to? Would we be able to start with something much smaller and then add on to the barn as we go? NOW IN NEW JERSEY

DEAR NOW: Yes, our buildings can be added on to. I would recommend the initial design be done with the idea of what the ultimate finished goal will be for size. Oftentimes, original structures are not structurally set up for the eventual expansion, which keeps the initial price low, but results in headaches and costs later, which could have been avoided with proper planning. A gabled roof will be the easiest roof style to work with when it comes to future expansion.

We have several customers who have done just as you suggest, adding on to one or both ends as they expand. Get the width you ultimately want, then adding length is much easier You can remove endwall siding, add on additional bays, and put the endwall siding back on. You may have to purchase more trims, but if steel siding, is easily reused for the addition.

And I always recommend – build as much building as you have space for and can afford economically, as whatever size you pick, it will never be large enough.

DEAR POLE BARN GURU: I’ve read ALL of your blogs!  Back to 2010. And love them. I write similar stuff in my business.

The question is do you have, or can you get, closures similar to ridge vent, but as a bottom closure to be used at the eave of a building without overhangs? BREEZY

DEAR BREEZY: Thank you for your dedicated readership and …good question! There is not such a beast, and even if there was, the net ventilation would be tiny – not enough to yield any positive results, as the only area which could have a vent would be just at the high ribs. The correct way to vent would really be with enclosed vented overhangs.

DEAR POLE BARN GURU:I have an existing pole building with badly deteriorating insulation and vapor barrier for the roof.

I plan to pull all of the old insulation and vapor barrier out to replace it.  I’d like to use the reflective radiant barrier / vapor barrier you recommend for new construction.  I’m considering pulling the metal roofing off to do it right so I don’t have to do it again later.

Do you recommend installing the reflective radiant barrier / vapor barrier between the metal roofing and purlins or between the purlins and roof trusses? DETERIORATING IN DELAWARE

Place the reflective radiant barrier over the purlins and directly under the roof steel. You will need to use larger diameter, longer screws to reattach the roof steel.

DEAR POLE BARN GURU:Where can I buy Owens Corning Foamular Fanfold foam 1/4″ thick? A lot of my fellow RC plane hobbyists are having a hard time finding this stuff. Thanks in advance. FLYING IN FREMONT                          DEAR FLYING: Visit the Contractor Desk of any The Home Depot®. If it is not in stock, it can be ordered in within a matter of just a few days.

Dear Pole Barn Guru: I Have a Roof Mold Problem

ADDED BLOG DAY!  Due to a large volume of questions to the Pole
Barn Guru, we are adding another day for answering questions – so look for more Pole Barn wisdom from The guru on Saturdays – starting – today! 

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays & Saturdays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday or Saturday segment.  If you would like 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: Have a 45′ wide x 120′ long by 20′ tall pole building.  All walls are insulated and covered with plywood sheathing.  Bottom cord of all trusses also sheathed with 1/2″ plywood.  Metal roofing is installed over felt paper that is installed over 1/2″ plywood roof sheathing.  Building has continuous ridge vent and multiple 10″x20″ soffit vents.  None the less we still have mold growing on the bottom side of the roof plywood. Here in Oregon we get ALOT of rain, so frequent moisture issues.  Should I add gable end fans?  Roof fans?  Thoughts. RAINING IN EUGENE

DEAR RAINING: Provided the underside of the ceiling plywood does not also have mold growth, then the moisture is an issue from the enclosed attic space. By Code, the requirement for attic ventilation is for 1/150th of the area of the attic to be in vents, provided at least 50% is in the upper ½ of the attic and at least three feet above the eave vents. This net free area is to be equally divided between the eave and the ridge.

In your case, the minimum requirement would be 18 square feet at both the eave and the ridge. My guess is your ridge is inadequately ventilated, thus the mold issue.

You should begin by replacing your current ridge with a product such as the Klauer Roofline Ridgolator 4 (www.https://klauer.com/metalcomponents.html). With 220 net square inches of free air per ten foot section – your 120 foot long ridge would provide just over the bare minimum required for proper exhaust.

Powered exhaust fans in each gable would certainly help, provided they are located towards the peaks of the gables, and have sufficient capacity to be able to pull air from 65 feet away.

DEAR POLE BARN GURU: What is the depth i should place my poles in the ground in concrete 24×48 10 feet tall not in city. SOMEWHERE IN SNOHOMISH

DEAR SOMEWHERE: As the county you are building in requires Building Permits for all structures the size of yours, and they do a structural plan check prior to issuing permits – you will need to go by whatever is on the approved plans.


Not knowing your design wind speed and exposure, dead loads on the building, roof slope and soil bearing properties, I can only say typically I would expect holes 40 inches deep, with the bottom 18” backfilled with premix. In the event you are constructing a “pavilion” style (all walls open), then it would be best to entirely backfill the holes with

Windows – A View To The World

I really, really like windows. They give a view to the world. They can be used for ventilation. Those are good things.

To bring those of you who are just joining my daily blog up to date, I’ve spent this week building a garage – in Happy Valley, Tennessee.  My thanks for the opportunity to get back into the building mode courtesy of my oldest step-son’s father-in-law.  Back to my saga of building in 100 degree heat and nearly 100% humidity….

Steve wanted to make certain there was plenty of natural light into his building. So it has six windows. Considering one wall has two 12 foot wide by 9 foot tall doors, it gives an idea of what was going to happen on the other walls.

From a building standpoint – windows are a pain. I will repeat, windows are a pain. Every window on this building took the cutting of two panels of wall steel to fit around it. The cutting was not so much of an issue. For me it was a case of measure about 100 times, before cutting. Every one of the window cutouts worked just perfect, no botched jobs.

The real challenge, is sliding the panels into place around the windows.

For this building, windows with built in J channels were ordered, which I always recommend. There is little more time consuming, or more prone to a future leak, than having to cut steel J channels to fit around windows.

The less than fun part is having to slide the panels into the J channel at the top of the walls, and above and below the windows.  And then getting the overlap of one panel to slide over the underlap of the previously installed panel.

In the past, I’ve used a putty knife placed between the panels to allow the new panel to slide up over the prior panel. In this case, we found a new trick….we had to cut small strips off a few of the soffit panels, so we took the cutoff vinyl strips and used them as sliding skids. Worked out neat and was less trouble than the putty knife method.

Come back tomorrow and I’ll finish up on my construction week for Steve’s new garage.  After a week of sweating in the hot mid-July sun of Tennesee, I’ll be looking forward to getting back to my air conditioned office!