Shop insulation and mold/mildew issue

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Feeling the Heat
Sep 15, 2016
Arlington Wa
Got a couple questions about my shop. It is a wooden pole building 24’x36’ with metal sides and roof on a concrete slab. Has an 8’x10’ roll up door and a 10’x12’ barn door with two man doors. The barn door will be changed out to a roll up door too. Has two 20”x4’ homemade type windows and an opaque corrugated strip around the 10’ mark to let some light in. Not sure of the age of it all.

Wondering if or what would be the best way to insulate it. It is unheated so it gets pretty cold in there in the winter time almost the same temps as the outside so anything to keep it somewhat warmer inside would be a plus. Issues I’m having is there are so many open areas where roof trusses go through and corners I’m just not sure what to do.

I’m assuming that vents would have to be added if all that was sealed but what would be the best route to take? If pictures are needed tell me of what and I’ll get them. I have plans to add a wood stove at some point in time for heat when I’m there but it would be nice if it would be warmer in there to begin with as about the only thing that it does now is shelter you from the wind and elements.

Also as of now things with cloth will start to mold or mildew. Not sure why if it’s moisture or humidity related but I don’t see dew or anything forming on walls or tools rusting. But when it rains water does come under the roll up door. Would that problem get worse after insulation or get better?

Overall just looking for better comfort when working out there in the winter time.

Lopi Rockport
Blaze King Ashford 25


Minister of Fire
Dec 2, 2017
Have you looked into spray foam? My opinion that is the only way to go.. Toss a ceiling fan up just to keep some air movement going you wont even notice that on your hydro bill. Or crack a window thats what i do in my shop


Minister of Fire
Dec 19, 2009
Eastern Ontario
I used Spray foam on my shop and have
never looked back . Warm in the winter
and cool in summer


Minister of Fire
Jun 23, 2014
Saratoga, NY
If you don't want to spend the money on spray foam, used foam board insulation can be a good option. Many places recycle it and you can get it for 10-20/sheet about 2" + thick.