Insulation prices

[ole farmerbuck]

We just had a 40x80 shop and 31x70 house built and are about ready for insulation. Anyone have a good outlet for some? Around here it's between .47-.53 sq ft. Thats R19. Suggestions?

 

[brunswick000]

I dont know what your budget is like, but I read an interesting article not long ago about using both diy sprayfoam and battan insulation for the best results. Sprayfoam to seal and provide marginal insulation and then battan on top. No need for vapour barrier either. Cant remember the exact R values for the combo but they were better than either type could provide on their own. Thinking about this for my garage this summer which is 30x50.

 

[Carl_NH]

I agree with brunswick. The closed cell spray foam is expensive, so do 1" of the closed cell to eliminate any air leakage/infiltration followed by batts or blown in. This will get the max r-value and tightest building for the money.

Of course the spray foam guys will want to do the whole 9 yards, so find a contractor that does both..

 

[brunswick000]

There are a number of building centers up North here that sell kits for the foam if your adventerous enough. I have a collegue who did it in his addition and said it wasnt too bad once you got going. Might save some money that way. It will actually add structural integrity as well as it seals and pulls everything together. Had a buddy from the east coast spray it in his attic rafters as he was converting it to another room. He then had to redo his roof the following year and the wood on the roof was so bad in some place that the foam was actually holding it together.....and quite well I might add. We had a pretty good laugh about it.

 

[brunswick000]

By the way.....40x80 garage. WOW! I have size envy...lol.

 

[Kyle_in_Tex]

Yah, the best is the spray in foam where they come back with a long blade and a sawzall and trim it flush with the uprights. I have a buddy who built a 3000 sq ft Texas ranch style home with porches all around. He claims his energy bills average only about $200 month. He spent almost $7000 I think having the spray in done. He also did a bunch of interior walls for sound proofing.

 

[milkman636]

3.5 " of high density closed cell foam cost me $1.70/sq.ft. of wall last fall. That price was installed of course. Blown in cellulose for the ceiling was basically $1/ cu.ft installed.

 

[ole farmerbuck]

Well the spray in sounds like the way to go but I dont know if wqe want to spend that much. We're getting in deep enough with the 31x70 house and full basement. There are a couple of places close to here that do the spray in. I guess it wouldnt hurt to get a quote for a couple of inches. Would I still have room for the 6" R 19 after 2" of spray in?

 

[mojoinco]

Hope this isn't too much of an 'opinion'. My observations have been that in a conventional stick built home the issue is getting a solid layer of insulation up on the outside of the studs and trusses. The places that stand out in the winter are where they are, as wood has a particular R value that you can't beat without there being some sort of 'break' layer. Which seems to be what is done with vinyl siding (likely not done for the advantage of insulation so much as it makes the siding hang and move better over the course of a year).

If it is a standard stick built house (and will work with your outside walls) I would consider a modest layer of sheet insulation as a thermal break layer (end of the day, what is the most effective for the money insulation). And plant wind breaks on the prevailing storm wind side of your home.

But that isn't what you asked -- you wanted to find a cheaper insulation source. Sorry, can't help, would like to see what you find.

 

[ole farmerbuck]

Hey mojoinco. They did install a layer of some kind of thin insulation or reflective stuff between the studs and metal.

 

[TRR]

I also saw the article on using spray and bat insulation together. Looked very promising, but did not read it in detail. One thing that stuck out though was that the thickness of the spray foam was important to control condensation from occuring in the bat insulation. And of course that depends on your local weather conditions.

The other thing about spray foam and diy. I checked the internet costs to do the spray foam myself and also had the local contractor bid the job. Turned out the local contractor charged something like 3 cents more per square foot, but installed 3 times the thickness the diy foam would do. So be sure you give the local contractor the chance to at least bid the job before you commit to diy.

 

[Carl_NH]

Hey mojoinco. They did install a layer of some kind of thin insulation or reflective stuff between the studs and metal.

So you have metal siding or roof? Usually its studs, followed by 1/2" plywood sheathing, then a barrier like tvek or a thin insulation, then the siding. If you have a thin insulation barrier between the plywood and siding thats a good thing and will reduce the air infiltration. Its the other areas where the materials meet that allow air in..

One comment and personal experience, I had the option to do this 15 yrs ago when spray foam was just coming out but opted (due to timing and cost) to use batt insulation. Well, we have a tight house, but still have airleaks / infiltration especially around the rafters/roof line area and other areas that would have been eliminated if we had gone the spray foam route.

I wish looking back I would have done the spray foam, and what you need to consider is this is the last time you will be able to do this realistically. It also sounds like you are in this place for the long term, so I would bite the bullet and use foam or some combination of foam and batts. You will reap the benefits in years to come.

Carl

 

[ole farmerbuck]

So you have metal siding or roof? Usually its studs, followed by 1/2" plywood sheathing, then a barrier like tvek or a thin insulation, then the siding. If you have a thin insulation barrier between the plywood and siding thats a good thing and will reduce the air infiltration. Its the other areas where the materials meet that allow air in..

One comment and personal experience, I had the option to do this 15 yrs ago when spray foam was just coming out but opted (due to timing and cost) to use batt insulation. Well, we have a tight house, but still have airleaks / infiltration especially around the rafters/roof line area and other areas that would have been eliminated if we had gone the spray foam route.

I wish looking back I would have done the spray foam, and what you need to consider is this is the last time you will be able to do this realistically. It also sounds like you are in this place for the long term, so I would bite the bullet and use foam or some combination of foam and batts. You will reap the benefits in years to come.

Carl

Its metal siding with no plywood. It has the thin insulation and then metal.

 

[milkman636]

I would be concerned about the fiberglass insulation turning into a warm bedding place for mice in the barn/shop. The slab-on-grade construction that is frequenly used lacks ratwalls and blocks above grade, the insulation is right down by the ground where it is easy for the mice to get into.

 

[KennyG]

An option I am using is polyiso foam. It's the (usually) brownish yellowish foam used by roofing contractors. Around our area it is sometimes available used in various thicknesses. The used stuff is in pretty good shape with a few large screw holes.

It usually goes for about $5 for a 4x8 sheet. The insulation value is about 50% better than the foam you get at the big box store and it is much easier to work with (cuts very clean). After you install it you can spray can foam the holes. I put 3-1/2" in my basement and have almost enough to put 5" in the walls of my 40x48 pole barn I'm rebuilding.

If you call some commercial roofing places you might find a source.

 

[boggen]

for the house. i would vote for a professional to come in and spray foam the entire house, walls and ceiling. and would most likely go with an open cell foam. to allow the walls and ceilings to breath a little bit.

if you doing insulation yourself in house. then most likely it would be the old rolled insulation. with vaper barrier. its cheap and it works.

for the shed. i would vote for a couple layers of hard board insulation, and at least one layer that has foil backing. and as i put the hardboard insulation, use a closed cell spray foam for me (i need to buy stock in the company way i used it last few years) great stuff red can with yellow cap. and use foil tap over all seems. the hardboard insulation can be cut out with a utilty knife or a steak knife if need be. and then patched backup. if a mice gets a hold of it. that and it tends to be more easier to tell were the blasted roadents came in through because you can see a trail of foam.

i wanted proffesional to come out and do the garage. but it automatically required that i put sheet rock or something over the spray foam. in order to meet code.

 

[Iplayfarmer]

I just insulated my basement ceiling and some walls. I had it blown in. The guy offered me an incredible deal to do my attic while he was here already doing the basement.

625 sq. ft. of 2X6 Joists
300 sq. ft. of 2X4 walls
700 sq. ft. of attic (R-39)

It all cost just about $1100. That comes to an average $0.68/sq. ft.