need some advice on insulating a steel building

[tininjun67]

Hey all,

I have a 30 x 60 r-panel building and I'm considering using the spray it green foam insulation. I work out of this building so I will have to do it one section at a time as i can't pull all of the stuff and equipment out at once and spray it all at once. A few questions:

1 How thick did you spray the wall and ceiling, and what are your experiences at that thickness as far as keeping temps out?

2 Are there any negatives to spray foam (closed cell) you've experienced?

3 I'm in central Texas and the winter temps are mild, however, some of the epoxy primers I spray require a minimum of 65 degree temp for a minimum of 24 hours. I will need to keep the building at that temp even when it's 30 degrees out. Any advice on foam thickness considering these conditions?


short term future plans include an electric furnace, long term include a geothermal system so i can cool in summer and heat in winter but that will be a long way off. I love the idea of a wood burning or waste oil burning furnace but flames can't be part of how i heat the building.

 

[Cjk]

I will be building a pole barn shop this winter and having the walls sprayed next spring with 2" closed cell and blown cellulose in the ceiling.

1. For the walls I'm told that once you get past 2" of CC foam your insulation value per dollar drops drasticly. We have been slowly updating our old farm house and I had the guy spray 2" on the exterior walls as we remodel rooms. The house is much warmer and less drafty. I was so impressed I will have the shop done the same. It really seals up nicely. The ceiling I would use cellulose as 6" or more of foam is going to be $$,$$$.

2. Most foam is flamable so will need to be covered. Will you be finishing the interior walls?

3. 35 degree rise doesnt sound like much with a decent heater in there if the rest of the building is sealed up.

 

[TurnipTruck]

I was told by my insulator anything past 3 inches (R21 total) is not cost effective. My deltaT is more like 90*F worst case, though. He also said the vapor perm doesn't reach 1 until just past 3".

 

[tininjun67]

I've been looking into the spray it green. It seems like a do all. Vapor barrier, flame retardant built in, etc. I do plan to finish the walls, not sure on the ceiling short term. Long term I would like the garage to be finished more like a hobby shop than work place. This is my everything: man cave, day job, toy storage, etc. I'm out here 7 days a week.