Insulation in a Barn

[uk-chris]

I have a two story barn, roughly 28x36, 2x6 construction with plywood then wood shingles on the outside. Right now there’s no insulation, I use it as an extra garage, workshop and storage. It has been ridiculously cold here in NH so I’m contemplating insulating it.

Trying to understand what would be cost effective and practical, I’d rather not put up drywall but don’t know how important it is to cover either fiberglass insulation / solid foam boards if I put them in.

My inclination is to estimate insulating the outside, if I do the walls and roof there doesn’t seem to be a great deal of point in insulating the ceiling/floor, likely to have propane run there soon and have the option to add a propane heater.

At a minimum I’d expect to cover the fiberglass with 6 mil plastic - is this sufficient for a detached barn?

Any suggestions on alternate approaches welcome, cost sensitive due to other priorities so I am aiming to do this on a budget.

Thanks,

Chris.

 

[NUTTSGT]

First of all, welcome to GJ. Secondly, you mention NH as your location, for future reference, I'd suggest you update your profile with that as your location. It'll help you get better advice per your location.


You mention 2x6 walls and cost sensitive, that latter rules out spray foam right now. I'd suggest start buying rolls of R19/21 with kraft paper and install it as you go. I'm not sure which big box store is in your area but most offer the deal on their credit card of spending $300 or more and getting it interest free for 6 months. This is also an option if you want to do it all at the same time. Otherwise, there is nothing wrong with buying as you go.

 

[Handyfarmer]

I lined my barn with oriented strand board, (wafer board), I bought a bunk of it when it was on sale,

it really helped stabilize the old building and gave a good wall, (no it not fire proof) but is very resistant to sparks and such when welding,

another option is to line it with roof sheeting tin, many use the white and it reflects light and looks very good, and is lightweight for it coverage,

i would cover the fiber glass batts with some thing, they tend to fall down if there not covered in time,

now covering it does not need to be done the day you insulate, but I would plan on sheeting the inside after insulation,

 

[stm317]

I'd imagine there's a lot of air moving through your building. Fiberglass doesn't do much to prevent air movement. I think I'd look into rigid foam panels personally. They tend to prevent air movement/drafts better than fiberglass.
If thick foam panels aren't in the budget, you can always combine thinner rigid foam on the sheathing and fiberglass inside that.

 

[xyster101]

Look over Craigslist for used ISO foam panels. They are replaced when a new roof goes on a commercial building. The price can be under $10 for a 2" thick 4x8 sheet. They are a little banged up, but provide the best insulation per inch of any foam sheet. It is a mess and pain to work with. You have to cut the fiber glass covering and cut each sheet to fit in between the studs.

 

[NotOrganized]

I had a house foamed recently (2015) and it was only 10% more than bats. Really surprised me so I jumped on it. Might be worth shipping insulation contractors.