Tag Archives: gutters

Wall Insulation for a Hybrid Building

Wall Insulation for a Hybrid Building

Reader MASON in HILLSBOROUGH writes:

“I read your blog often and I truly appreciate the wealth of knowledge you openly share. I am in the process of starting construction on a hybrid steel shop that will house a small apartment that the wife and I will move into once its finished. We will sell our current home and then build a smaller house adjacent to the shop. 50 X 80 with 24′ wide mezzanine on one end. My questions are centered around wall/roof construction as well as proper insulation. Roof: I plan to install a standing seam roof with ice/water shield over 5/8 plywood. As you are aware, with hybrid steel it is hard to ventilate the roof with this type of construction. This downfall didn’t outweigh some of the benefits so this is what I am stuck with. Would like to understand some insulation options. Note: I do have the building designed to handle the loading of a couple of cupula’s and have considered making these passive and active ventilation points. (Exhaust fans with some louvers that I have yet to get the details figured out on)Walls (2 options): (Note: I prefer not to plan or have to always be fully conditioning the shop to 72 degrees…..I plan to have that ability by mechanical means but I don’t want to consistently have to be conditioning that much space, therefore I think i prefer the building to be able to breath out to the perimeter. I realize this may be tricky between the roof type and wall type)Option 1: metal siding – would like some input on wall and insulation construction based on the above notes of conditioning. Option 2: Hardie board vertical board and batten walls. Same as above, would like your input. There will be components on the first floor and second floor that make up the apartment space. Our approach on insulation and wall construction may change within those enclosed spaces may vary as they will be conditioned separately from the open shop space. Hope you can help shed some light on this approach and again thank you for your time and knowledge. Thanks!”

Thank you very much for your kind words!

In Orange County, being Climate Zone 3A, I would most often recommend drying to inside, using closed cell spray foam to insulate underside of roof deck and applied directly to wall steel. This does entail having to mechanically dehumidify.

Given your desire to dry walls to exterior, here are my thoughts:

Have a well-sealed vapor barrier under your slab on grade – you want as little moisture as possible entering building.

Include eave overhangs of at least two feet – this is again about moisture. You want to push weather (water) away from base of building.

Install continuous gutters, draining at least 10 feet away from building foot print.

For wall construction – regardless of siding being used, place a drainable housewrap under siding (make sure it is omnidirectional, so you can install either vertically or horizontally). Use bookshelf wall girts to minimize deflection and create an insulation cavity. Unfaced Rockwool insulation to completely fill insulation cavity. Well-sealed interior vapor barrier.

Zero Lot Line Post Frame Construction

There are occasions where the best location to place a building just happens to be right up to a lot line. Let’s face realities – if your site’s required setbacks without fire resistive construction are five feet, what is going to accumulate in this area? Most often it is either “stuff” or weeds, neither of these being aesthetically pleasing.

Reader CLINT in SPOKANE, is faced with this and writes:

“I have a unique question regarding a firewall.  In Spokane County you are allowed to build up to the property line of your neighbor given that you have a 1hr rated fire wall from both sides on the property line.  (2hrs total).  I’ll attach a copy to the code requirements.  To meet code apparently you have to use “type x” drywall on both the interior and exterior of the wall.  I understand the install and have even read up on your reference to a 3hr firewall from some time ago.  My question is, how do you weather-proof the exterior drywall? It seems that putting metal siding directly over-top the drywall could lead to moisture damage.  I’m guessing that even if it is OK for most of the wall what about the lower ground level part?  Do you need a vapor barrier or special trim/flashing to prevent splash damage from ground level. Or maybe even humidity alone could be bad?  I’ve seen what drywall does with water so that is my concern with it being only a metal layer away from the elements. Thanks for your help!”

Mike the Pole Barn Guru advises:

While your copy of Spokane County’s requirements did not make it, I am fairly familiar with them as I was once their most prolific post frame building contractor (built over 200 buildings in Spokane County in a single year).

To reach two hours, you should have two layers of 5/8″ Type X on each side of your framed wall. You also need to insure any rain or snow coming off your roof does not land in your neighbor’s yard. This will entail a slight setback to allow for gutters and you will need a snow retention system on this side of your roof (this is assuming we are discussing an eave side and not an endwall).

Start with investing in “green board” 5/8″ Type X drywall. While not waterproof, it is moisture-resistant. It is available from providers such as GTS Interior Supply in Spokane. You should use a Weather Resistant Barrier (WRB) on your exterior between drywall and steel siding. Screws for steel should be three inches in length for this wall, in order to get adequate penetration into wall girts. Base trim (aka rat guard) can be special ordered with a longer flat leg to seal off water splash up from ground. Mineral (rock) wool insulation should be used in this wall, as it is not affected by moisture.

Extended reading about NFBA’s three hour firewall testing can be found at https://www.hansenpolebuildings.com/2012/03/firewall/

Stilt Post Frame on Permafrost

I have written previously about post frame design involving concrete slabs on grade in areas of permafrost: https://www.hansenpolebuildings.com/2018/04/post-frame-permafrost/. Today we will venture into a land where “stilts” are a design solution.

Permafrost is loosely defined as soil and/or rock remaining frozen for more than two years. Big trees do not guarantee an absence of permafrost; it might just mean permanently frozen ground or ice is down far enough so soils in those spots can support a larger root system. Only way to be certain of what ground contains is to have a soils test drilling done.

With permafrost, a safe bet is to it avoid it altogether and move to another piece of land. This is easier said than done, particularly because of a scarcity of affordable buildable land. If you decide to build on permafrost, be as strategic as possible. Smaller and simpler structures will tend to fare better than larger, more complicated ones.

Minimal site disturbance is an accepted practice. Trees and ground cover are your best friend. They protect and insulate ground from summer’s heat. A great example is green moss you find on many shaded low-level areas. Moss has a high insulating value, and in many cases if you dig down a couple of feet, ground might still be frozen in middle of summer.

Strategies for construction on permafrost include:

  • As a general rule, organic layer of ground cover provides insulation and should not be removed, as this will increase risks of thawing any frozen ground underneath.
  • Elevate and properly insulate bottom of your post frame building to prevent floor system heat losses from reaching ground underneath, leading to thawing.
  • Use a thick gravel pad significantly wider than post frame building itself (also insulated if possible) to stabilize the ground and spread building loads.
  • Embed columns to a depth able to both support the structure and resist frost jacking from seasonal ground movement.
  • Cut trees sparingly to maximize site shading (while permitting for a fire break).
  • Build a wrap-around porch, which will help shade the ground around and underneath your post frame building.
  • Incorporate large roof overhangs to shed water away from building and provide shade.
  • Install gutters and manage site drainage well away from building.
  • Retain a geotechnical engineer familiar with local soil’s conditions to assist in designing a foundation system adequate to safely support your post frame building on soils specific to your site.
  • Septic systems also must be engineered to function on permafrost, and remember conventional systems might risk thawing the ground.    

More information on permafrost is available at these websites:

If you have a question, contact the Cold Climate Housing Research Center at info@cchrc.org or 1(907)457-3454.

Building Instructions, Gutters and Spouts, and Crinkle!

DEAR POLE BARN GURU: I love your site and have used your detailed instructions to start my pole building. I wish I had found your site before I started. 

I was wondering if you sell partial pole building kits? I have been going back and forth to the lumber store several times a week and it’s getting old. I’m at the step of having the purlins up and working on getting the purlin blocks in place. I would need the rest of the materials.


DEAR JOSH: Thank you very much for your kind words, we are pleased you have found us to be of assistance. Sadly, your experience is one we hear far too often – those trips back and forth to the lumber yard end up being time consuming, when your efforts could be better spent being able to be actually making progress. We really are not set up to be able to take and work from a client’s partially constructed project and take it through to the end for them – there are just too many variables which could cause the project to turn out to be less than what you and we expected. If you need technical assistance or advice, going forward, please feel free to ask and we will do our best to assist you.


DEAR POLE BARN GURU: Have a quote from Hansen. Are gutters & downspouts included in the premium trim package? VAN in CINCINNATI

DEAR VAN: Gutters and downspouts are frankly just not practical for anyone to include in a post frame building kit package. In order to do so, we would have to ship you pieces – most usually ten feet in length or less. This leads to lots of seams and if gutters are going to fail and leak, they will most often do so at seams.

The way to go is truly with seamless gutters. Here is some additional reading for you on this subject:


DEAR POLE BARN GURU: I am intrigued by the Valspar Crinkle finish coating. Can this be added to a metal barn roof, or does it have to be done at the factory? SUNNY in WOODLAND

DEAR SUNNY: I am intrigued by it also. We have yet to have a client invest in the Crinkle finish, or even inquire about it. In my humble opinion it is due to lack of awareness upon the public. For whatever reason, our industry is fairly slow to offer new features to clients and our own staff is probably just as equally negligent in not having at least advised their clients as to it being an available option.

In answer to your question, it is not a retrofit, it is a product which is painted in a factory.

For more reading: https://www.hansenpolebuildings.com/2017/03/crinkle-finish-steel-roofing-siding/



Dear Pole Barn Guru: Will a Drain System Hurt My Piers?

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. 

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com


I have a 40′ L X 30′ W metal pole barn, which has a 10′ overhang.  Basically the foot print is 40 X 40.  The roof has a 6/12 pitch that is connected to the overhang roof, which transitions to about a 3/12 pitch.  I live near Buffalo, New York and have a problem with gutters on the overhang.  Every year the snow wants to pull down the gutters.  I don’t really like the idea of putting up snow jacks because it’s just more holes that I’m putting in the roof and I feel like I would be compromising the integrity of the roof over time.  I have read about the use of French drains and though I would just eliminate the gutter on that side and install a French drain.  I’m wondering if I “opened up a can of worms” and would be causing more problems than it’s worth.

I dug a trench about 18″ wide and 24″ deep along the side of the pole barn.  My plan is to place #2 clean washed stone with perforated SDR35 pipe in the trench leading out to ground level on the slope behind the barn.  The drain pipe will be wrapped with a filter sock and the stone surrounding the pipe will be wrapped with designed trench filter paper.  This should prevent silt from entering both the stone and also the pipe.

My concern is not so much with the design of the French drain, it is more with the pole barn piers.  Will I be compromising my piers with this drain system?  When I dug the trench I went down about 2′ next to the footings all along the one side.  Am I now creating a frost or heaving problem with those pier footings?  I would appreciate your help before I create a problem here.  Thanks. Darien Dan

DEAR DAN: Without having a geotechnical engineer personally visit and inspect your building site, I can only give generalized answers, so here goes….

Will you compromise your piers with this drain system – it is possible. The extra water being added into the ground system could cause not only frost heave issues, but could also contribute to settling of the columns. Besides potential frost heave and settling issues – the drain system is not probably overly economical in either time or cash outlay.

Provided your roof system was properly designed for the added weight, there are several polycarbonate snow retention systems for roofs which will not cause you to have to put any more holes in your roof. A special adhesive is used to glue the snow guards to the steel roof surface. Once installed, snow should adequately stay on your roof, keeping the gutters where they belong, instead of on the ground next to your building.


DEAR POLE BARN GURU:  Can fink truss 6″ pitch  and 24 ft span  be on 2 ft centers. Inquiring in Arkansas.

DEAR INQUIRING: In background – a “fink” style truss is one in which the interior truss members (or webs) are in the shape of a “W”. In some cases, it is referenced by the number of “panels” (spaces between the truss webs) from one side of the truss to the other. In the case of a fink truss, the top chord would have four divisions, the bottom chord three.

A 6” pitch is one where the sloped top chord of the truss, gains six inches vertically, for every 12 inches of horizontal movement.

As to whether your span, slope and spacing combination will work or not, would depend upon the design loads which the truss is expected to carry. These loads include sloped roof snow load, dead loads from roofing, sheathing, insulation, ceiling materials, etc., as well as wind loads.

To be safest, take your complete building plans to the prefabricated wood roof truss manufacturer of your choice and they should be able to use this information to design and quote the project.

Seamless in Seattle: Rain Gutters

I just could not resist this title. This article is not a plug for the business which actually uses this name in Seattle, it just caused a chuckle. Rather like the hair stylists, Curl Up and Dye.

guttersThe main purpose of rain gutters is to protect a building’s foundation by channeling water away from its base. They also help to reduce erosion, prevent leaks in basements and crawlspaces, protect painted surfaces by reducing exposure to water, and provide a means to collect rainwater for later use.

In many building permit issuing jurisdictions, gutters are a requirement on any new building.

Water collected by a rain gutter is fed, usually via a downspout, from the roof edge to the base of the building where it is either discharged or collected. Collection systems for water carried from rain gutters may include a rain barrel or a cistern.

Excess water near the foundation of a building can cause settling. With the widely spaced columns of a pole building, a settled post can cause noticeable visual humps along the eave line. Repeated or prolonged exposure to moisture also creates susceptibility to mold, mildew and decay.

Properly functioning rain gutters channel harmful rain water and snow melt away from building foundations.

About ¾ of all rain gutters installed in the U.S. are made of seamless aluminum.  At a moderate cost, they will last the lifetime of the building and are rust resistant, even when subjected to standing water for prolonged periods of time.

Seamless is somewhat of a misnomer – as seams do exist where gutters meet at corners or downspouts. It does afford fewer places where leaks could potentially occur.

This type of gutter cannot be done as a D-I-Y project, as they are formed out of flat coil stock by a gutter machine.

My personal experience is the gutter industry is very competitive. When I had the seamless continuous rain gutters and downspouts put on my own house and pole building garage, I was amazed at how reasonably priced they were.

There are lots of places to save money, when it comes to a pole building project however, in my opinion, trying to do rain gutters other than seamless is not the place to scrimp.