Insulation

[kehrli3]

Greetings guys,
This is my first post. I am about to pull the trigger on a 40x50x10 pole building for a garage. I live in NE PA. I am having my builder finish the ceiling with the white steel panels and then do the R30 blown insulation. I am not having them finish the walls so I can do the electrical, etc. I see so many different opinions on how to insulate the walls. I will be putting heat in it eventually as my budget permits. I'm just confused on the vapor barrier, etc. My original thought was to just stud the walls between the posts and do R19 in the studs. I will be finishing the walls with OSB plywood. Please educate me on the correct way to do this with budget in mind. Pardon my ignorance, this is my first pole building and just trying to do the right thing. Thanks much for your help and input!

 

[Steevo]

Your posts will be 6" deep, so go with that when you stud between them, and you can get at least R21 batts in there.
There is no substitute for excellent insulation.

 

[Slowgsr]

Insulation is important but more important is having a tight building, vapour barrier needs to be sealed very well, air loss defeats the purpose of high insulation.

Most of your heat loss goes up, I suggest r50-60 in the attic, and your idea with 2x6s @ 16" oc is a good plan, I'm not a fan of osb/plywood since a tight taping Job on drywall is one more step to less air loss, also I'm very concerned with fire rating since I do cut with a torch and weld occasionally, but I have zero storage on the floor, less places for sparks to smoulder.

I would have gone with 2x6s when I studded my walls but my building was leaning (fairly old)so I went with 2x4s to level the walls and loose minimal space. So I only have r14 (all roxul), but against the metal prior to studding the previous owner had cut the pink foam board to fit tightly against the metal, my guess is to prevent sweating previously.

 

[kehrli3]

Thank you for your replies! If I just stud out with 2x6 or even 2x4, do I need to do a vapor barrier? If so, does the vapor/moisture barrier go on after stud and insulation. In other words, the vapor barrier should be between my insulation and my osb?

 

[Slowgsr]

What's your climate, where are you from? Will your building be wrapped before the metal sheeting goes on the outside?

 

[Rookie2]

With steel o/s panels you need house wrap or spray foam insulation.

 

[HeavyD1]

Why would he need spray foam or house wrap? Couldn't you do fiberglass bats with vapor barrier to the inside?

 

[sandslot]

Isn't closed cell foam (maybe 1-2" thick) good to preempt some Glas bat in a 2x6 wall? I'd think it would remove any air gaps.

 

[Rookie2]

Why would he need spray foam or house wrap? Couldn't you do fiberglass bats with vapor barrier to the inside?

Those o/s metal panels have seams,they usually seal the top and bottom but wind will enter the vertical seam and kill your R-value. Most insulation is installed too loose to keep air out .

 

[tfinniii]

Putting a Tyvek material in bays first before studding will help air from drafting thru insulation.

 

[yaidunno]

House wrap the outside prior to tin. Hang 8' wide bats of insulation (or what ever width your pole spacing is). Vapor barrier the inside before whatever you sheet the wall with.

I'm in process of doing just this on my 36x48x12. Wall insulation came in at $900.

 

[bzinsky]

best value for dollar, house wrap + bats
best performance foam

Just a theory of mine, no evidence, but I'd think taking a few cans of spray foam and putting a bead around the wall cavity, where the studs meet the exterior walls, would be highly beneficial. Not only seal gaps, but it would decrease the amount of gaps from the insulation as the bat corners would be pressed onto the foam. Probably also strengthen the structure since the studs would also essentially be glued to the exterior wall.

 

[kehrli3]

Thank you all for your input. Much appreciated.

Sent from my SAMSUNG-SM-G870A using Tapatalk

 

[James-W]

If you plan on staying where you are for many years, I would certainly look into the cost of doing the spray foam insulation. It certainly will be more expensive, but since you are heating/cooling the building it would pay for itself at some point down the road. I realize you said you had a budget and spray foam would probably cost quite a bit over the budget, but still, if you can manage it, I think in the long run you would happy you did it.

 

[dmcintosh]

I'm in the process of insulating my pole building and decided to NOT use foam (partially because it is expensive, and in my research read about metal rusting out down the line wit spray foam. In retrospect I probably should have had the building wrapped before the metal was put up, but I did not. I decided to go wit 2x6 in between the posts 16" OC. Planning to use fiberglass bats, likely with a plastic vapor barrier on the inside behind the drywall. Snapped a few pictures while I was finishing up for the day.

 

[Slowgsr]

I prefer roxul, doesn't hold water, rodents won't use it for nesting and its fire proof, also less itchy.
I did my roof ceiling strapping with 1x4 after the insulation/vb. air gap between drywall and vb. probably isn't needed,

I'm also a big fan of full 5/8 fire code, and 3 coat tape, and acoustic sealant, fire stop around any drywall penetrations, etc. Just to make it as air tight as possible.

I too didn't wrap the outside prior to tin due to age since the building was existing,

 

[dfiler2]

Thank you for your replies! If I just stud out with 2x6 or even 2x4, do I need to do a vapor barrier? If so, does the vapor/moisture barrier go on after stud and insulation. In other words, the vapor barrier should be between my insulation and my osb?

Correct, the vapor barrier goes between the insulation and your OSB always on the warm side of the building. The vapor barrier is there to stop moisture from getting inside your walls. House wrap is not a vapor barrier but it is very important it helps stop air infiltration and products like Tyvek allow any moisture that does get into the walls to escape. IMO using both with have a pretty quick payback.