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Raka025
03-04-2010, 10:16 AM
Does anyone have experience with the do-it-yourself kits that are available? Is it cost effective? I have half the garage/shop walls left, the ceiling (30' x 48' x 6") and the eventual attic space to do and tend to work in small chunks of time. Are nozzles and equipment reusable or do they get tossed after the application like those small cans do?

Thanks for any and all considerations or experience...

huisjen
03-04-2010, 10:24 AM
Experience? No, but...

I've been thinking about using some of that stuff too. It costs about $1.00 per board foot, which is about twice what blue foam board costs. When I do my big project with it, I intend to fill most of the space with foam board, then seal it all in with spray. My understanding is that there are disposable tips and ways to seal up the gun, sometimes coating things with vasaline before packing them away. When thinking about price performance, don't just think of it as insulation. It's major function is air sealing. Compare the price to what it would take to fill and caulk all the gaps using caulk and backing bead.

Dan

StevenBauer
03-04-2010, 10:24 AM
I helped a client spray one of the 600 sq. ft. kits that he ordered over the web. It cost about $650. It came with hoses, gun and a bunch of tips. All disposable. It only took an hour or so to spray the kit, it was easy and kind of fun.

I am finishing off the space over my garage and want to use the foam to get a perfect air seal between the garage and the living space above. I called a pro outfit and their price to spray it was the same as the DIY kits. About $1 a sq. ft. per inch. Some people just spray an inch or two for an air seal then put in some fiberglass to fill the rest of the cavity.
I'll take some pics when they come to spray. :)


Steven

katey
03-04-2010, 10:44 AM
A friend who is building a house says that because of the discount that the contractors get, it's a financial wash whether you have it applied or do it yourself.

John of Phoenix
03-04-2010, 10:51 AM
This might qualify for a tax credit if that "cash for caulkers" program goes through.

stoneyreef
03-04-2010, 12:05 PM
Here we get an $800 rebate if you add insulation.

I just had it all bid out and to retro foam my house it was $4600. YIKES!!! So I decided to get an energy audit done with thermal imaging and see where my polystyrene beads have compacted and just re-blow beads.

Mrleft8
03-04-2010, 12:11 PM
Be careful... That stuff can blow siding off the house, crush plastic junction boxes, bow door frames/window frames jamming them, etc. It's also a pain to clean up.

Ron Williamson
03-04-2010, 12:42 PM
x2 on the pain to clean up.
I watched a foam newbie do a 30x60 window frame.
He dropped the can in the first second.
On it's way down, it scraped across the jamb and sash(to be finished clear), then down the screen and the glass(new low-e coatings),then the can hit the sill(leaving a sweet half-moon.Being of quick reflexes, he stuck out his foot a bit too late to slow it down,hitting the trigger, and ended up punting it across the room pinwheeling a big goober of foam.
R

Michael D. Storey
03-04-2010, 01:07 PM
I have had great luck over the last 20 years with blown in cellulose. Price is right, no toxins, etc. The R of foam is not as good. Foam is about sealing cracks, etc.

chas
03-04-2010, 02:30 PM
Be careful with the use of spray foam as an air sealer in wood-frame construction. Wood framing will expand and contract during seasonal changes in humidity, not to mention shrinkage associated with new construction. This is one of the forces that serves to sever the attachment of foam to framing and creates cracks that allow the passage of air.

If the foam is part of the air-barrior that should be an integral part of your exterior cladding design these cracks may allow moisture penetration during incidences of extreme wind loading, which in itself may cause some degree of structural movement.

Of more concern is when the foam is used as part of the moisture-barrior that is installed on the warm side of the insulation in your wall cavities. The cracking associated with it’s use here, particularly around windows and exterior doors whose use eventually implies some degree of movement in their framing, will allow moisture-laden heated air into the spaces between window/door and the surrounding framing. In cold climates this can result in the formation of condensation, usually found at the base of the window/door framing and on the bottom plates of exterior walls. Rot is the eventual result.

One would need to know the particulars of your wall and roof framing, Rob, to ascertain the most cost effective method of insulation. Perhaps the lower overall humidity levels experienced in Arkansas will allow options not viable in other areas.

A 30x48 shop; colour me green with envy. / Jim

StevenBauer
03-04-2010, 02:40 PM
He dropped the can in the first second.


I think we're talking about two part foam systems here, Ron. There is no can to drop. Either two bbq size tanks with 25' hoses (the DIY case) or a trailer with 55 gallon drums (the pro spayer case).




I have had great luck over the last 20 years with blown in cellulose. Price is right, no toxins, etc. The R of foam is not as good. Foam is about sealing cracks, etc.

The newer dense pack cellulose systems are very good but the R-value is still not as good as the foam systems. If you aren't using a dense pack machine the R-value of cellulose isn't even close. Dense pack machines are not the kind they rent out at the big box stores.


Steven

Breakaway
03-04-2010, 02:46 PM
Question: Does the cellulose (paper? ) encourage mold or bugs compared to foam, or f'glass?

rbgarr
03-04-2010, 02:58 PM
If the outside envelope of the house leaks water (around windows, doors etc.) the cellulose can get moldy and compacted.

Bob Cleek
03-04-2010, 03:04 PM
Or you can just wear a warm sweater on those especially cold days. LOL

StevenBauer
03-04-2010, 03:07 PM
The cellulose is treated with borates to keep out bugs and such. If it is installed with the newer high power dense pack blowers there is no way it could be compacted or settle in any way. It's just in there too tight for that to happen.

Steven

StevenBauer
03-04-2010, 03:11 PM
Or you can just wear a warm sweater on those especially cold days. LOL

Ha ha. When I blew in 10 inches of dense pack to my attic and 6 inches into the sloping ceilings of the second floor of my house my heating oil consumption went from 1500 gallons a season to 500. About $2500 saving per winter at $2.50 a gallon but two winters ago oil peaked at $4.85. :eek: And I'm sure it will be there again. :(


Steven

paladin
03-04-2010, 04:31 PM
As noted above, use caution. The material expands and 1 hour after you walk away sometimes will start expanding again. I had several of the kits when shipping large quantities of my hardware overseas. I sprayed the bottom of a large box and let it sit for 3-4 hours, then placed the electronics in the box, all in a smaller box with a plastic bag around it, then foamed the box in place. All hardware arrived safe and sound.

Raka025
03-04-2010, 05:15 PM
Thanks everyone for your thoughts. The bays are presently open with no interior sheathing so the blown in would be out. I would also suspect that the path of least resistance would not blow out the exterior siding? With all the advice, it is now a passing thought and no doubt I will pass. One of the contractors has some recycled cellulose/cotton that is blue and fits in like regular insulation without the foil or paper backing. It doesn't itch and is pretty dense. I forget what the R-value is? You can see recycled jeans pieces in it.

Probably a sweater would be cheaper and a close second would be to hook up the radiant floor heat. It felt like spring today so maybe by next fall...

I just worked a road out in the woods to the biggest white oak tree I have found on the property. It has a 7' circumference. It should be good for a few floors, maybe some deadwood, doubtful for the keel.

B_B
03-04-2010, 05:31 PM
where does one rent/buy these types of DIY kits?

seafox
03-04-2010, 05:33 PM
how is it dense pack cellolous of higher R value than regular? I thought it was the air traped in it that did the job of slowing heat movement. if it is packed then their is less air???

Raka025
03-04-2010, 06:18 PM
where does one rent/buy these types of DIY kits?

You can do a search as I had done.

reddog
03-04-2010, 06:41 PM
Braam, DOW has one kit called the 'Froth Pack' I believe. Available in different size kits for various applications. Be sure to read the MSDS sheets with any of these foams as some require positive pressure air supplied respirators when installing. BASF makes a medium density product, 'Walltite Eco, but sell it only to licensed,factory trained installers. I've been seeing increased use of these products in buildings I inspect but tend to be a bit skeptical until I can get some 'real world' performance data. Remember you are spraying your house full of a plastic material with all the inherent chemical compounds.

Earl

StevenBauer
03-04-2010, 06:48 PM
where does one rent/buy these types of DIY kits?

Google Spray Foam Insulation.




how is it dense pack cellolous of higher R value than regular? I thought it was the air traped in it that did the job of slowing heat movement. if it is packed then their is less air???

I think it's because it completely stops the movement of air inside the wall cavity.

There is lots of good info at www.buildingscience.com

Steven

StevenBauer
03-04-2010, 06:52 PM
As noted above, use caution. The material expands and 1 hour after you walk away sometimes will start expanding again.


The stuff we used cured pretty fast. Once the two chemicals are mixed the reaction is pretty much done in 5 minutes. I guess it might be a problem if you went too thick at once. For really thick applications you have to let it cure and cool then come back to it.


Steven

reddog
03-04-2010, 06:54 PM
seafox,a few years back they found that by slightly increasing the density of an insulation you can also increase the R-Value for a given thickness.However it rapidly reaches a point of compaction where the numbers reverse and you quickly lose any gains. You are correct in the statement that insulation is air held in place but it is subject to factors such as convection movement through the insulation itself. This ,I believe, is where the compaction helps by slowing this down.One example, here in Nova Scotia we have just adopted energy code requirements which state exterior wood frame walls are to be insulated to R-24.The previous standard was R-20 for which a 6" batt of glass fibre insulation was used. Lo and behold, Owens-Corning came out with a R-24 batt which will fit in standard 2x6 wall construction.A compressed batt. The spray foams perform exceptionally well, as mentioned above, because they pretty well eliminate air movement through the wall or ceiling assembly. ;)

Earl

oznabrag
03-04-2010, 07:01 PM
I had occasion to supervise the construction of a large house a couple of years ago, and the foam quote was based on the use of a product that was 95% agriculturally derived, and it was about a dollar a board foot.

The dense-pack cellulose was cheaper, but we ran into problems with the stuff drying out. The walls were 10" thick on the North side of the house, and I had to run heaters and fans for a week to dry them out to a point where I felt good about drywall.

So...Huisjen, when you priced your blue foam-board, how thick was your spec? I'm pretty sure they make that stuff up to about 6". It may help on the price. Took a little stroll through Google, and I came
up with this awesome used-insulation site:

http://www.insulationdepot.com/

Awesome!

StevenBauer
03-04-2010, 07:23 PM
The dense-pack cellulose was cheaper, but we ran into problems with the stuff drying out. The walls were 10" thick on the North side of the house, and I had to run heaters and fans for a week to dry them out to a point where I felt good about drywall.

There is a dense pack cellulose technique that uses a latex binder but there is also a dry technique. The contractor I use uses the dry method so that has never been a problem for me.


The bays are presently open with no interior sheathing so the blown in would be out.

Actually this isn't true. What they do is staple a reinforced poly to the face of the studs then angle lots of staples into the edge of the studs pulling the poly tight. Like a drum tight. Then they just cut a small X in the poly to insert their hose. I'll look later to see if I have any pictures.

Steven

oznabrag
03-04-2010, 07:30 PM
There is a dense pack cellulose technique that uses a latex binder but there is also a dry technique, also. The contractor I use uses the dry method so that has never been a problem for me.



Actually this isn't true. What they do is staple a reinforced poly to the face of the studs then angle lots of staples into the edge of the studs pulling the poly tight. Like a drum tight. Then they just cut a small X in the poly to insert their hose. I'll look later to see if I have any pictures.

Steven

The contractor we hired used a borate/water mix at the nozzle , and raked off the excess with a roller/brush on a guide. Just 'planed' it off at the level of the stud.

reddog
03-04-2010, 07:46 PM
Up here the cellulose insulation is usually used for flat or low slope ceilings although I have seen a couple of places with it blown into wall cavities. In those cases a fine mesh was fastened to the studs and the product blown in similar to how Steven described.
Onzabrag,there is one spray foam being used locally that is supposed to be soya based. It is a low density product so has less insulation and air sealing values than the medium density foams but may be less toxic to install. As I stated above I tend to be skeptical of these products until they have a proven track record in our area. Back in the 1980's the Canadian government gave grants to homeowners to spray their walls and ceilings full of UFFI foam. This was a formaldehyde base product which produced varying reactions in people ranging from mild irritation to severe. A few years later they paid people to have the stuff removed. Believe me it was way more expensive taking the stuff out.

Earl

oznabrag
03-04-2010, 08:20 PM
... Back in the 1980's the Canadian government gave grants to homeowners to spray their walls and ceilings full of UFFI foam. This was a formaldehyde base product which produced varying reactions in people ranging from mild irritation to severe. A few years later they paid people to have the stuff removed. Believe me it was way more expensive taking the stuff out.

Earl

Oh, believe me, I believe you!