Tag Archives: glulaminated column

Spray Foam, Crawl Space Floors, and Column Sizes for Shed

This week the Pole Barn Guru answers reader questions about spray foam application of a vapor barrier, finishing a crawl space floor, and to go with 3 ply or 4 ply columns– this is dependent upon many things.

DEAR POLE BARN GURU: New Construction – Can spray foam insulation be spray over a vapor barrier blanket in the roof of a pole barn, too increase insulation rating?

Thank you, TERRY in WILSONVILLE

DEAR TERRY: In your part of our world, most often roof condensation is controlled by use of what is known as a “Condensation Control Blanket” – a thin layer of fiberglass bonded to a white vinyl backing. When laps are properly sealed (rarely done right) it does make for an effective vapor barrier, although it provides minimal, at best, insulating value.

I am not a fan of spray foaming to any flexible barrier in walls or roofs (https://www.hansenpolebuildings.com/2020/04/spray-foam-insulation-3/).

My first choice would be to design your building to be capable of supporting a ceiling, use raised heel trusses and blow in fiberglass insulation. With raised heel trusses you can get full thickness from wall-to-wall and you do not end up heating dead space between roof trusses. Roof steel should be ordered with a Integral Condensation Control (https://www.hansenpolebuildings.com/2020/09/integral-condensation-control-2/) and adequate ventilation provided at eaves and ridge.

Second choice would be to omit condensation blanket and Integral Condensation Control and use two inches or more of closed cell spray foam directly to underside of roof steel. This will not be nearly as effective as choice number one.

 

DEAR POLE BARN GURU: After reading several articles on your website I’m leaning towards building a single story post frame home with about a 4 foot crawl space so that I get benefits of a floor not hard on the joints and access to any plumbing or electrical if things go wrong. I would also like to build as close to a passive or net zero home (within a reasonable budget) but was wondering how to do that with a dirt floor crawl space. I’ve read that the best way is to keep crawl space within the envelope of the home but I’ve only read of a vapor barrier that is covering the dirt floor. Thanks for all your help. TODD in HENNING

DEAR TODD: Thank you for being a loyal reader. My knees and your joints must be related – as nothing pains me more than standing on a concrete floor for even relatively short periods of time.

Most crawl spaces are created with dirt floors, face it, they are low budget and meet Code with a 6mil black Visqueen Vapor Barrier installed. Now retired Hansen Pole Buildings’ Designer Rick Carr built himself a hunting cabin over a crawl space a year ago and decided to take a slightly different route. He opted to do a thin layer of concrete to cover ground in his crawl space, with an idea of being able to roll around using a mechanic’s creeper, should he need to work on sub-floor utilities. Here is an excerpt from part of Rick’s planning: https://www.hansenpolebuildings.com/2019/03/pole-barn-cabin-part-ii/

 

DEAR POLE BARN GURU: I am putting up a 60x135machine shed. 18 ft sidewalls, I’m wondering if the 3 2×8 laminated columns are enough or if i should spend 2900.00 more to go to 4 2×8 columns. thanks, SHANE in ASHTON

DEAR SHANE: Your question leads me to believe you are attempting to make a hundred thousand dollar plus building investment, without benefit of fully engineered structural plans.

Column sizes will be dictated by effects of column spacing, design wind speed and exposure (an Exposure C site being subjected to 20% greater wind forces), roof snow loads, dead weight of roof system (including any ceiling), roof slope as well as proper diaphragm design of your building shell.

I will implore you to please, please, please build only from a fully engineered plan. Think of it as an investment into one-time insurance. I only want to see you put this building up one time.

PermaColumns, Pole Barn Planning, and Insulating a Roof

This Monday the Pole Barn Guru discusses the use of PermaColumns, planning of a pole barn in Florida, and the best solution for a building without roof or exterior wall weather resistant barriers.

DEAR POLE BARN GURU: I am having a pole building put up with engineered laminated columns. The contractor is pushing a “Perma Column” made up of concrete and welded rebar that goes in the ground, about 5′ long surrounded by more concrete, and the laminated columns are bolted on top through 1/4″ steel brackets. My question is, are these laminated columns OK to go directly into the ground, with concrete, or is it important to keep them out of the ground as these Perma Columns would do? TIM in MEDICAL LAKE

DEAR TIM: Back in my post frame building contractor days we built many a building in and around Medical Lake.

Hopefully those columns are true glu-laminated columns, as opposed to nailed together. Most of these are designed specifically for post frame construction and have their lower six or more feet pressure preservative treated for structural in ground use. If this is your case, there is no issue with their lower end being embedded directly in ground (reducing costs and increasing ease of construction). While precast Permacolumns would keep columns out of ground, there is a better option – https://www.hansenpolebuildings.com/2018/04/perma-column-price-advantage/

 

DEAR POLE BARN GURU: Hello. We are planning to build a pole barn home in Arcadia, Florida. We were looking into the 40 x 60 with 2 leans on the sides. However, we cannot find someone who specializes in these constructions and can tell us how to start, what type of foundation is needed since it’s a pole barn. Do you do the entire project or you just supply the kit? Do you have contractors you work with as far as installation? Please get back to me asap. ANA MARIA in NAPLES

DEAR ANA MARIA: Well, you have reached out to where you should be, as Hansen Pole Buildings specializes in post frame homes (barndominiums and shouses).

Links in this article will get you through budgeting, financing, finding property, room design and floor plans: https://www.hansenpolebuildings.com/2019/10/show-me-your-barndominium-plans-please/.

Post frame foundations can be as simple as properly pressure preservative treated columns embedded in ground, to columns mounted to engineered brackets or even continuous footings and foundations.

Our buildings are designed for the average physically capable person who can and will read instructions to successfully construct their own beautiful buildings (and many of our clients do DIY). Our buildings come with full 24” x 36” blueprints detailing the location and attachment of every piece, a 500 page fully illustrated step-by-step installation manual, as well as unlimited technical support from people who have actually built buildings. For those without the time or inclination, we have an extensive independent Builder Network covering the contiguous 48 states. We can assist you in getting erection labor pricing as well as introducing you to potential builders. We would appreciate the opportunity to participate in your new home. Please email your building plans, site address and best contact number to Caleb@HansenPoleBuildings.com.

 

DEAR POLE BARN GURU: Have a 30×42 pole shed at my new home that I purchased. It is partitioned into 2 parts, a back room (30×12) and front (30×30). The back room is finished off with OSB on the walls, in between the horizontal 2×6 purlins there is 1.5″ unfaced rigid foam board (expanded polystyrene I believe) and on the ceiling it appears that it is just a rock wool type insulation between the purlins and a 6 mil plastic vapor barrier stapled to the purlins along the bottoms all the way around the room. There is crosses cut into it every so often (assuming for a vent). The room is heated by a Propane wall heater and it gets Very warm and holds heat very well even with it being open to the 16 ft. peak. This room has been like that for 25+ years and it shows no signs of condensation, rust, rot, or anything for that matter. The front section (30×30) has 1.5″ RTech faced rigid foam boards between the horizontal girts with the foil sides facing into the shop & seams spray foamed etc. The 30×30 room will be heated with a vented 75k BTU unit heater that is also run off of LP. Side note- The building has no WRB between the steel and “studs” on the walls or roof. My question is how can the roof be insulated without the use of spray foam or removing the metal and wrapping it. I am looking for all the feasible options for this project, thank you. JACKSON in COLEMAN

DEAR JACKSON: Providing your building’s trusses are designed to support weight of a ceiling and any non-conditioned dead attic space above can be adequately vented, your best bet is to install a ceiling (my preference would be 5/8″ Type X gypsum wall board) and blow in fiberglass insulation. This will be your most cost effective alternative in materials and labor and will result in a minimum amount of space to be heated.

 

 

Taking the Bow Out of a Glulaminated Column

Taking the Bow Out of a Glulaminated Column

Glulaminated post frame building columns are touted by their producers as being able to withstand warping and twisting. On occasion, however, they will bow.

Hansen Pole Buildings’ client JOSH is self-building in SALMON, Idaho and wrote:

“Good Morning Mike,

Thought I would check with you, but probably know the answer already.

Is there any way to deal with a glulam post with a bow in it, aside from replacing it?

And if replacing, I can get one locally without pressure treatment. I presume since I am in Sturdi Wall brackets, that makes it OK… but would hate to find out from the inspector it has to be PT after the fact.

Thank you.”


Mike the Pole Barn Guru responds:

I had previously written about how one of our clients had taken twists out of solid sawn ncolumns here: https://www.hansenpolebuildings.com/2015/08/pressure-treated-post/. But, I had never previously shared how to un-bow a bow.

I shared this with Josh:

This is how we used to straighten bowed solid sawn timbers when I owned lumberyards.

Assuming it is bowed in a single direction – support it at each side of the bow, with bow up. Thoroughly saturate bowed area with water (as in seriously soaked), then put weight on at the center of the bow – enough to bring board to straight (we used to use a unit of lumber). Allow to dry and it will be straight.

Josh happened to have a nearby place where he could saturate this errant column.

And, while he did not have an ability to move a unit of lumber to perform Step #2, he did use Idaho ingenuity:


He reports, “Working well so far”!

Josh is building what will be an absolutely amazing post frame home – we will be looking forward to sharing photos as work progresses!