Spray Foam Insulation - Information comparison

[n74tg]

I've looked at several different alternatives for spraying my own foam insulation on my house.  I was prompted to do this information survey because the costs of having someone come in and spray 2# closed cell foam were prohibitive, and according to the reading I've done (mostly on the Buildingscience.com website, plus others) despite what the open cell contractors claim, using 0.5# open cell foam just won't do what I want (moisture and airflow barrier).

Of course there are all the what I will call the "DIY propane can" suppliers (TigerFoam, FoamItGreen, etc).  They all run about $1.00 per bd-ft of finished foam.  As I need 2-2.5" thickness that will run about $2.50 per sq ft insulated.  I have altogether about 4400 sf to insulate, resulting in roughly 10,000 bd-ft of material needed, or about $10,000 cost if using "propane cans".  To me, downside of the propane cans is no pressurization maintenance system which will result in me having to slow down as each can empties.  Upside of this system is that the cans are disposable when finished.

Source of Supply (in Polyurethane) has a SSP 1000  and  1000 N system, designed for contractors/builders or other medium sized operations where you don't want to invest $20 - 30k in equipment.  The SSP 1000 system has heated hoses (for use in colder climates), the 1000N hoses are unheated.  As inside temps in my project are already reaching 90 I'm not worried about having unheated hoses.  A positive pressure respirator system comes with the equipment and they require training by one of their staff (not free).  I don't have a cost on the training yet.  The 1000 system costs $3475, the 1000N system, $2350.  Both systems use compressed nitrogen bottles instead of a air compressor (bottle regulators included in system cost).  Foam runs about .69 per bd-ft.

Soythane makes a 1.5# closed cell foam.  Their system is a little different in that you use disposable canisters in to the gun that mix and shoot the foam.  Each canister covers about 30 bd-ft, ie roughly a 6' x5' area.  You buy the foam by the case (6 canisters per case).  Foam runs about .80 per bd-ft.  For my roughly 10,000 bd-ft needs, I'll have to buy a total of 60 cases, shipping to be $650 (unless I can work a better deal).

So far, and all data is not yet in, seemingly best deal from a cost viewpoint is the Soythane, followed by 1000 N system, each of those being cheaper than the "propane tanks" approach.  With the 1000 N system you have equipment that you have to keep up with, store, maintain after the job is complete, so this system is probably better for a contractor than a person building just one house, like many of us are.

Other opinions welcome.  If you have any experience with any of these (or other) alternatives, I'd love to hear them.







 

[n74tg]

I didn't mention it but I will most likely be using a "flash and batt" approach.  My sources indicate that whatever R-value you plan to build too, that 50% of that R-value should be in foam.  So, an R-19 wall needs roughly R-10 in foam, the other R-9 can be fiberglass or whatever else you choose to use.  The purpose of having 50% of the total R-value in foam is to insure that the dew point temp is never reached inside the fiberglass, but always reached inside the foam (where no condensation can occur, in CC foam).  Or, stated another way, with the dew point temp inside the foam, the boundary between foam and fiberglass will always be above the dew point temp, so no condensation occurs. 

[rocking23nf]

I just dont see the gain in using spray foam when you factor in the costs. Sure its probably a superior product. But is our current products that bad? Take my house for example. I live in Edmonton alberta, house is 15 years old, we range from +30 in the summer, to -40 in the winter, celcuis.

My house is complely done with yellow insulation in 2x6 walls, its 1600 square feet, and has a proper vapour barrier.

My furnace is natural gas, and my heating bills in the winter is around 125$, with a good 50$ of that being user and government fees.

So lets assume my house was 100% spray foamed. how much better could I possibly get? 115 a month? 120 a month? 

I personally would not even consider spray foam until the price comes down to near the price of batt insulation.

Now show me some data that guarentees my heating bill will be cut in half, and sign me up.

[psammy]

wow $2.50/sf!  is that just the foam or does that include the 'batt'?  my local foam contractor charges $2.67/sf for full-depth 2x8 roofs....materials & labor (1/2# foam).  be careful with the 2# foam that you don't create a moisture trap between the foam and roofing.  i've heard other opinions on 'flash & batt' that 3" of 1/2# foam and the rest blown cellulose makes for a good non-vented roof insulation system.  it almost guarantees the roof can dry to the interior without a moisture trap, and the cellulose can manage any moisture much better than FG.

psammy

[pagan]

n74tg,

You could always buy the professional equipment and sell it after you've done all of your insulation. How long will the nitrogen last amd how much does it cost to replace?


My 16 X 20 cabin with a full loft, 2 ft. knee wall, is closed cell foam and I use a little more than one cord of wood per year. That's using an old Waterford Stanely cookstove.

[n74tg]

Celt:
The nitrogen is probably the cheapest part of the whole deal.  One bottle, approx 225 cft goes for I think $18 and will do one set of 55 gal drums worth of foam.

[pagan]

That is good. How much do you think you could get selling it after you're done?

[n74tg]

I have no idea what I could sell it for.  Additionally, I don't know that I would want too.  I can't really give you a good reason why right now.

One thing I did find out about this system is that it has only been available for sale on the market now for about 3 months.  That bothers me a little as they may not yet have all the bugs worked out.  If this system had been in use for 2 years or so, it would be a different story.  Also, it's new status on the market would make it difficult to find other purchasers whom I could talk too.  The supplier says there are plenty to be found in the New York, New Jersey area, but none in my home state, or for that matter surrounding states.

Right now, I'm kinda leaning towards the Soythane.  They have been in business awhile.