Insulating shop building

[Bobby Robbinett]

Being in the south I don’t have to deal with a lot of cold weather. Summer is very hard on me because I have to take some medications that make me very sensitive to the heat. I have ended up in the hospital several times with severe heat exhaustion and almost having a heat stroke several times in the past 10 years. With that being said, I want to insulate my shop for the purposes of air conditioning.

I already have a 5 ton r410a unit on the north side and a 3 ton r410a on the south end. The larger 5 ton unit is ducted out about 15 feet into the shop away from the return intake. I haven’t finished installing the 3 ton unit on the other end, but will set it up similarly.

My shop is an all red iron metal building built in the 1960’s and insulated with standard 48” wide typical 3” or so thick faced fiberglass insulation. This original insulation is falling off the ceilings and several parts of the walls. I had to repair a bunch of leaks in the ceiling that went unnoticed and unattended to until I moved in 2 years ago. That really messed up a lot of the insulation on the ceiling. My plan is to cut out all of the places on most of the ceiling and so basically spot repairs on the walls until perhaps one day I can afford spray foam.

My questions to you guys are:
#1 where is the best place price wise to purchase 3” thick 48” wide insulation that would typically be for a metal building?

#2: what can I use to hang this stuff? I know there has to be like a strap type material to retrofit this stuff, but I am not sure what it’s called or where you get it?

#3: any advice would be welcomed.

[Tom Bender]

Bobby, can you post a picture? We can help better if we know what you are talking about.

5 tons of a/c is a lot for a small shop but may be too little for a huge barn.

3" of fiberglass sounds pretty good for a/c, not so much for heating in a cold climate.

[james manutes]

I'm in upper Arkansas . Had a 4 ton AC unit that cost a fortune to use . Installed a mini split and the monthly savings paid for it in less than 1 year . What's it cost for those 2 units combined in July , Aug. , etc.. ?

[David Walser]

Bobby -- I cannot answer your question about where to purchase the insulation bats. However, I have a couple of suggestions that might help others help you: First, it would help to know where you're located. Insulation may be rather light, but it is bulky, which may make it difficult for an out-of-state supplier to compete, after shipping costs, with someone local to you. Second, you might also want to check with local installers to see how much it might cost for them to do the job for you. They buy insulation in bulk at a significant discount. Often, what they charge to insulate a building is less than what it would cost to do it yourself. Obviously, that depends on your local market and on the size of the job, but it's worth checking out. Again, if we knew where you were located and the size of your building, someone on the board might be able to help you.

Good luck!

[Bobby Robbinett]

Bobby, can you post a picture? We can help better if we know what you are talking about.

5 tons of a/c is a lot for a small shop but may be too little for a huge barn.

3" of fiberglass sounds pretty good for a/c, not so much for heating in a cold climate.

I don’t have the ability to post pics yet. I need to sit down and sign up as a paying member sometime this weekend so that I can post pics.

My shop is an odd shape and design. It is roughly 90ft x 70ft with a 25ft x 25ft space for an office and a 16ft x 16ft paint room and an 8ft x 8ft spray booth. Not all of it is 90ft long or 70ft wide. The actual usable space is about 4,500sq/ft roughly give or take.

[Bobby Robbinett]

Bobby -- I cannot answer your question about where to purchase the insulation bats. However, I have a couple of suggestions that might help others help you: First, it would help to know where you're located. Insulation may be rather light, but it is bulky, which may make it difficult for an out-of-state supplier to compete, after shipping costs, with someone local to you. Second, you might also want to check with local installers to see how much it might cost for them to do the job for you. They buy insulation in bulk at a significant discount. Often, what they charge to insulate a building is less than what it would cost to do it yourself. Obviously, that depends on your local market and on the size of the job, but it's worth checking out. Again, if we knew where you were located and the size of your building, someone on the board might be able to help you.

Good luck!

Thank you for the advice David.

I actually do intend to check and see if I can find any insulation contractors as you are correct about the fact that it could wind up cheaper to have someone like that do it than for me to do it myself.

I am in a rural part north east Arkansas. I have a buddy that does spray foam and he charges $1.48 per sq/ft for closed cell foam which is as you pointed out, cheaper than I can buy it for.

I know the Manards sells 65ft long x 48” wide rolls for roughly $216 per roll. To do my entire ceiling would take roughly 19 or so rolls so just under $5,000 with tax. Closed cell foam would be under $6,900 and would have the benefits of sealing any leaks and keep insects and bugs out better and make it a whole heck of a lot easier to cool off when it gets hot. Problem is that is more than I can afford at the moment. I would like to find a solution in the $2,000 to $3,000 range but that might be a pipe dream.

[roger wiegand]

You might constrain cost by focusing on your southern and western exposures-- or wherever the sun most hits the building. The considerations are a little different for a cooling than heat. Especially with a metal building a lot of your heat gain may be coming from the sun hitting the building and radiating inward. In that case even one inch of closed cell foam on those walls/roof section might give you a big benefit. Remember you need to provide either enclosure of intumescent paint for fire control if you go with spray foam, the paint is easy but not cheap. At the roof you will surly benefit from venting the roof if you go with conventional insulation--provide a path for the very hot air that will form between the roof and insulation material to escape

[Jim Becker]

Bobby, no question that I would personally use the closed cell spray foam...it has a lot of benefits beyond just insulating and at the price you can get it, no brainer.

[Charles Coolidge]

Bobby, no question that I would personally use the closed cell spray foam...it has a lot of benefits beyond just insulating and at the price you can get it, no brainer.

Jim is there any increased risk of fire with the spray foam. Or is it fire retardant perhaps? Seems like Holmes on Homes uses spray foam a lot on the show. I ask after driving past a major home fire in our town yesterday which got me thinking about the shop I'm going to have built soon.

[Jim Becker]

Closed cell spray foam can be and most often is infused with fire retarder and can be left exposed. It's that way in our home addition...the whole attic is part of the conditioned envelope. It's one of the nice things about using it in metal buildings as it removes the cost of covering the insulation and it can even be painted.

[Jamie Buxton]

If you're a one-man shop, you could wall off part of the building, and insulate only that smaller part. You'd do most of your work in there. The remainder of the 4500 sqft building could be storage, or could be for operations which you do very rarely.