Trying to figure out the cost of having a 1500 square foot metal building spray foam insulated. The living area will be 900 s.f. while the shop will be 600 s.f.

Pardon me for being dumb on the subject, but from what I have read, I won't need closed cell in the living area because the foam will not be exposed and will be covered up by walls (pine bead board), but in the shop area, where the insulation would be exposed, I would need closed cell?

Also, I have kicked this idea around, since I am trying to be as economical as possible on this barndo build, of buying the D.I.Y. spray from insulation kits and taking the task on myself. Has anybody done this? How big of a nightmare is it to do? Would one be better off paying a professional to do this?

TIA

The DIY kits are super easy to use. I have done 4 major projects with them and it was one of the easiest parts of the project, IMO. Buy a little more than you need and maybe practice first so you do not waste any and can learn the technique.

Hoyt Ag said:

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The DIY kits are super easy to use. I have done 4 major projects with them and it was one of the easiest parts of the project, IMO. Buy a little more than you need and maybe practice first so you do not waste any and can learn the technique.

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Which kit did you use?

http://www.ebay.com/itm/Touch-n-Seal-U2-600-Fire-******ant-Closed-Foam-Spray-Foam-Insulation-Kit-600BF-/391048543648?hash=item5b0c4f3da0

I used closed and open from this company. I thought it was a good value and good product.

Appreciate the suggestion! It's looking like I will be taking on this task myself. So one and a half kits of open cell for the living area should cover the 900 s.f.. Then one kit of the closed cell should take care of my shop. Hopefully I won't bite off more than I can chew and I save myself a good bit of money by the DIY approach.

I didn't look at the link Hoyt put - but almost every kit that I looked at prior to doing my attic gables list their coverage at 1" thick. So if they claim 1000 SF coverage, that's 1000 SF at 1" thick or about 300 SF at 3" thick. Keep that in mind.

Also, because the shop is still enclosed, I don't see a need to go with closed cell personally. May be a smidge better option, and if there is an insulation guru here they will hopefully chime in, but closed cell is best suited in an area that will actually be exposed to elements (subflooring in a pier and beam house, etc.).

The installation is fairly easy - once you get the hang of how to spray and at what rate, it goes fast. The tanks are heavy as hell though. There is a place on the north side of Houston that has them in stock at a great price, was very happy with the service and kits I bought there when I did mine.

Did you apply a thicker layer of foam than what was recommended? Or just go with what the kit says and go 1" thick?

We sprayed 1.5" average coverage and it keeps my cabin well insulated, IMO. Our house was done with 3".

http://www.akuratedynamics.com/

Dirty-8-thirty Ag said:

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Did you apply a thicker layer of foam than what was recommended? Or just go with what the kit says and go 1" thick?

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Spray in coats - it rises and sets quick, so once you get done with a section of wall, you go back to where you started and spray another coat on top. You don't want to spray too thick initially because it ******s the expansion and set up time. 3 coats of 1" thick yields a better install than trying to do a single coat 3" thick.

It takes about the same amount of time anyway.

These guys have been recommended in the past on the H&I board. Foam it Green

As far as the foam thickness, typical attic insulation is R-30 in Texas. The closed cell spray foams are in the R-7/inch area and the open cells are around half of that. R-30 with closed cell would be 5" and 9" with open cell.

Where are you located?

I am having my shop sprayed next week with 3" of open cell on all walls and windows. 1600 sf total. Walls will be covered, ceiling exposed. What schmellba99 said is correct. Open cell is just fine on any surface not exposed to elements.


The cost for my job is $1/ft. so $1600 total. That DIY kit posted would be far more expensive if I am reading it correctly. Even though you wouldn't need as many inches (due to being closed cell) you'd still pay more for the DIY kit. Not to mention the guy that is doing my install is going to shave the excess off, and clean up after himself. Its pretty much turn key.

Edit: The contractor that is doing my job quoted me $1900 for 1" of closed cell. The R-value of 1" of closed cell is substantially less than the R-value of 3" of open.

Wall, TX.

East of San Angelo on 87 about 13 miles.

I am waiting to hear back on quotes from a few different guys. I was thinking that it would be way more expensive when done by someone else, but I guess it makes sense that they could do it cheaper since their cost for materials will be much cheaper than mine.

I was all set to do the green foam recommended on the H&I board but dcided to shop rates. I paid $950 for 3" in the wall and 5" in the ceiling of my 15x20 shop, open cell.

I was also told that open cell is a better sound absorber than close cell which will make a difference in a shop with a metal roof.

http://www.eskimoinsulation.com/

Aggie-owned and operated. Terrific Family. Ask for the owner Robert

That's a long way from Wall, TX

No doubt. Missed that post. Carry on.

My BIL does this for a living. He is in Angelo. I can get you in touch with him if you need another quote.

That would be great.

Aggietaco said:

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These guys have been recommended in the past on the H&I board. Foam it Green

As far as the foam thickness, typical attic insulation is R-30 in Texas. The closed cell spray foams are in the R-7/inch area and the open cells are around half of that. R-30 with closed cell would be 5" and 9" with open cell.

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Foam insulation is a tough thing to explain when compared to typical insulation. I work in hvac and I've never seen more than 5.5 inches of open cell.

I cant explain exactly why, but in a foam house, the amount of an needed is about 60% of a traditionally insulated house of the same size. The r value of the foam isn't as important as the sealing of the envelope. That's the way it's been explained to me at least. Like a beer cooler. The r value is lower than something I could make with batt insulation but it insulates better because it's a sealed envelope.

Agreed that there is typically less R-value in the foam insulation projects that I've seen, but I did tour a house that a friend built last year with 8" of open cell in the attic here in Austin. And the reason why you can get away with less insulation is that 4" of open cell or 1" of closed cell foam acts as an air barrier.

LGAggie said:

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Aggietaco said:

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These guys have been recommended in the past on the H&I board. Foam it Green

As far as the foam thickness, typical attic insulation is R-30 in Texas. The closed cell spray foams are in the R-7/inch area and the open cells are around half of that. R-30 with closed cell would be 5" and 9" with open cell.

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Foam insulation is a tough thing to explain when compared to typical insulation. I work in hvac and I've never seen more than 5.5 inches of open cell.

I cant explain exactly why, but in a foam house, the amount of an needed is about 60% of a traditionally insulated house of the same size. The r value of the foam isn't as important as the sealing of the envelope. That's the way it's been explained to me at least. Like a beer cooler. The r value is lower than something I could make with batt insulation but it insulates better because it's a sealed envelope.

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Batt insulation looses its R value over time, same with the blown in. Foam doesn't, and as mentioned - it does a much better job at sealing the structure from outside air infiltration.

Question -
On new construction, would you do walls and underside of roof?
Or walls and floor of attic?
Or all three?

I suppose all three would be most effective, but maybe not necessary.

Texas 1836 said:

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Question -
On new construction, would you do walls and underside of roof?
Or walls and floor of attic?
Or all three?

I suppose all three would be most effective, but maybe not necessary.

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Walls and underside of roof. Doing all 3 is really a waste.

But you need to make sure your HVAC designer knows what type of insulation system you are doing. An oversized HVAC unit is horribly inefficient and doesn't run enough to pull moisture out of the air properly, leading to mold and what not.

Texas 1836 said:

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Question -
On new construction, would you do walls and underside of roof?
Or walls and floor of attic?
Or all three?

I suppose all three would be most effective, but maybe not necessary.

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I would build with a conditioned attic space which means all of your mechanical and plumbing equipment needs to be selected with direct vent or sealed combustion options. Placing ducts, mechanical equipment, lighting, exhaust fans, etc, in an unconditioned attic space in the South is a terrible idea. Getting all of that equipment into a conditioned space will help it last longer and work more efficiently. Not to mention you don't have to worry about air sealing every little penetration into the living space from the attic.

schmellba99 said:

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Texas 1836 said:

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Question -
On new construction, would you do walls and underside of roof?
Or walls and floor of attic?
Or all three?

I suppose all three would be most effective, but maybe not necessary.

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Walls and underside of roof. Doing all 3 is really a waste.

But you need to make sure your HVAC designer knows what type of insulation system you are doing. An oversized HVAC unit is horribly inefficient and doesn't run enough to pull moisture out of the air properly, leading to mold and what not.

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You mean 400 sqft/ton ain't good enough for you?

What type of a/c should I run in the build? Would it be better to do a conventional system or a mini split? Also, what size system would I need to properly heat and cool a 900 s.f. area?

How would a mini split work with two bedrooms and no ducting? Would one just need to leave the doors open to not get too hot or cold?

I plan on having a wood burning stove for winter time heating. I have just always thought they were so badass.

My shop is 640sf and I am installing a mini split.

Check out garagejournal.com in the heating and A/C section. Tons of good advice over there.

Nothing like a little Kentucky windage with your most expensive appliance, is there?

There are multi unit mini splits that should work.

schmellba99 said:

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Texas 1836 said:

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Question -
On new construction, would you do walls and underside of roof?
Or walls and floor of attic?
Or all three?

I suppose all three would be most effective, but maybe not necessary.

---

Walls and underside of roof. Doing all 3 is really a waste.

But you need to make sure your HVAC designer knows what type of insulation system you are doing. An oversized HVAC unit is horribly inefficient and doesn't run enough to pull moisture out of the air properly, leading to mold and what not.

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If you are building new, the HVAC contractor should do a tonnage load, or have one done. We use a lady in Houston (we are in Cen TX) who's sole occupation is calculating how much air needs to go in a structure. She takes insulation type and r value, window and door type and number, occupancy, roof type, cardinal orientation, and who knows what else all into account, factors it all in, and tells us exactly how much air is needed in each room. She hasn't missed yet.

I say "should" but really, if they can't show you the load work up, you need to find another contractor. There are too many variables now to go by any kind of sqft/ton metric.

What about of closed cell and open?

Shoot an inch of closed first to seal it. Then come back with open cell on top of that to fill the space.

Texas 1836 said:

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What about of closed cell and open?

Shoot an inch of closed first to seal it. Then come back with open cell on top of that to fill the space.

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A popular option is to use 1" of closed for the air barrier aspects and then come back with standard batts or loose fill, depending on the application.

For Hvac you want to do a "manual j" calculation

http://www.loadcalc.net/