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Mon Jan 25, 2010 11:12 am

wee need to insulate our 60 year old house. I have heard about the spray foam that we can use for the attic and subfloor, and also the pour in foam for the exterior walls.

Does anyone know where to get the product for a DIY project?

Mon Jan 25, 2010 11:34 am

Careful trying to do foam yourself. You can blow the sheet rock/plaster right off the walls.
For DIY, you would be better off doing blown in cellulose insulation.
Also, do you have fire stops in your walls, or is is ballon framing.

Mon Jan 25, 2010 11:36 am

Have you tried This Old House or a website dedicated to home repair?

Mon Jan 25, 2010 11:38 am

I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

Mon Jan 25, 2010 5:09 pm

we are most likely going this route with our new house. it will probably be impossible to do if your walls are closed in (as in sheetrocked/plastered) you are most likely screwed. as mentioned, the process involves spraying a expaning foam in the cavity, then shaving it off. the other thing you need to do with foam (in new construction) is anchor any wires to the exterior plywood, because it will push it out toward the sheetrock. also, you have to tape and caulk any electric boxes, otherwise, the stuff will creep in to the box and make a huge mess.

your best bet may be the blown in cellulose, it sounds like you are doing a retrofit. check this old house and the DOE insulation fact sheet, tons of good info

Mon Jan 25, 2010 5:20 pm

The spray foam is extremely flammable! It starts with an invisible flame! I have seen bad things happen!

Mon Jan 25, 2010 5:53 pm

The foam itself is not very flammable once it is cured. It is the carrier chemicals that are flammable.

There is a pour-in style that can be used in existing walls, but the blown in cellulose may be a better answer. The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there. It is very efficient, though, and makes for a very low permeability for air and vapor.

Mon Jan 25, 2010 5:57 pm

Ok, the carrier is bad stuff!

Mon Jan 25, 2010 7:34 pm

wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

Mon Jan 25, 2010 8:42 pm

millerje78 wrote: wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

cdennisg wrote: The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there.

Do I hear an echo? :wink:

Mon Jan 25, 2010 8:47 pm

cdennisg wrote: millerje78 wrote: wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

cdennisg wrote: The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there.

Do I hear an echo? :wink:

yeah, I jumped the gun before reading all the posts. :lol:

Mon Jan 25, 2010 9:29 pm

I don't recommend it for anything except for making molds for producing small to medium-sized items made of wax, certain kinds of rubber, fiberglass, polyresin, coldcast bronze, ceramic, Plaster of Paris and concrete (in other words, nothing in four-digit Fahrenheit temperatures in a molten state, like glass or metal), for sealing spaces around water and compressed-air pipes and for homemade archery targets, due to the flammability of the carrier chemicals and wet foam. The difficulty of getting to wires, studs and pipes after the foam is dry, as mentioned above, is another strike against spray-on foam for its primary intended purpose.

I recommend fiberglass insulation or vermiculite, since it can be moved about easily, is fairly inexpensive and is a bit more tolerant of inexperienced installers. Just keep in mind that protective gear is necessary with the fiberglass and that asbestos can (very) occasionally be found in vermiculite. The cellulose mentioned above is another good choice, but I know next to nothing about it.

Just my 2 cents there,

OG

Mon Jan 25, 2010 9:43 pm

Old Grimey wrote: The cellulose mentioned above is another good choice, but I know next to nothing about it.

the cellulose stacks up to fiberglass as far as R-value goes, and its about 25% cheaper. Also noteworth is its made from recycled materials.

NOTE: when using cellulose in the stud bays: you should use a "wet" glue admixture in the blow-in procedure to keep the cellulose from sagging over time, which will create an insulation void in the top portion of the stud bay. gravity will create this void.

Mon Jan 25, 2010 9:43 pm

I think we have vermiculite and fiberglass in our ceiling.... rethinking the foam idea.

Mon Jan 25, 2010 10:06 pm

millerje78 wrote: cdennisg wrote: millerje78 wrote: wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

cdennisg wrote: The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there.

Do I hear an echo? :wink:

yeah, I jumped the gun before reading all the posts. :lol:

boy, how rumors spread. the cured state of foam insulation is that of a stale marshmallow. any good electrician or plumber with the correct snake (usually a fiberglass one) will have no issues with it at all, and i have been told by a few electrician they prefer foam insulation beacuse it is easier to push through, where fiberglass insulation can and usually does bunch up, making it useless in the R value department. i am no pro, but have read and talked to more people that deal with it on a daily basis, and almost everyone (plumbers, electricians, etc) will debunk all the myth's

Mon Jan 25, 2010 10:17 pm

skills@eurocarsplus wrote: millerje78 wrote: cdennisg wrote: millerje78 wrote: wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

cdennisg wrote: The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there.

Do I hear an echo? :wink:

yeah, I jumped the gun before reading all the posts. :lol:

boy, how rumors spread. the cured state of foam insulation is that of a stale marshmallow. any good electrician or plumber with the correct snake (usually a fiberglass one) will have no issues with it at all, and i have been told by a few electrician they prefer foam insulation beacuse it is easier to push through, where fiberglass insulation can and usually does bunch up, making it useless in the R value department. i am no pro, but have read and talked to more people that deal with it on a daily basis, and almost everyone (plumbers, electricians, etc) will debunk all the myth's

As a carpenter who spends time around folks in the other trades, I have heard exactly the opposite. I have never personally worked with the stuff, though.

Mon Jan 25, 2010 10:23 pm

Old Grimey wrote:
I recommend fiberglass insulation or vermiculite, since it can be moved about easily, is fairly inexpensive and is a bit more tolerant of inexperienced installers. Just keep in mind that protective gear is necessary with the fiberglass and that asbestos can (very) occasionally be found in vermiculite. The cellulose mentioned above is another good choice, but I know next to nothing about it.

Just my 2 cents there,

OG

Vermiculite does contain asbestos, and does cause asbestosis and mesothelioma. If you have it in your house, leave it alone. It is fine in it's undisturbed state. IF you must remove it, do so with great precaution, or better yet hire a professional that is licensed to do so. Do not mess around with this crap.

Google W.R. Grace if you want to know what havoc this stuff has wrecked on the town of Libby, MT. I would never recommend using it when other, safer alternatives are so readily available.

BTW, there is some about five feet above my head right now.

Tue Jan 26, 2010 2:05 pm

skills@eurocarsplus wrote: millerje78 wrote: cdennisg wrote: millerje78 wrote: wgargan wrote: I am aware of the blown out wall situation, but I think there is a slow fill foam and with the right calculations it should be ok. but i am still on the fence about the foam or celulose.

good idea about this old house, i'll check it out.

this is only my opinion of course, but I wouldn't use the foam in an older home. if you ever feel the need to add outlets, switches or make any other electrical or plumbing changes, you have shot yourself in the foot with foam. Is your home plaster and lathe with wood clapboard siding?

cdennisg wrote: The only thing I don't like about the spray-in foam is that it is very difficult to make any changes to wiring and plumbing once the foam is in there.

Do I hear an echo? :wink:

yeah, I jumped the gun before reading all the posts. :lol:

boy, how rumors spread. the cured state of foam insulation is that of a stale marshmallow. any good electrician or plumber with the correct snake (usually a fiberglass one) will have no issues with it at all, and i have been told by a few electrician they prefer foam insulation beacuse it is easier to push through, where fiberglass insulation can and usually does bunch up, making it useless in the R value department. i am no pro, but have read and talked to more people that deal with it on a daily basis, and almost everyone (plumbers, electricians, etc) will debunk all the myth's

its not a rumor brother. Its personal experience (commercial contracting). The cured state of foam insulation is a PITA, and I'd like to meet the guy that can "aim" a snake down a 9' stud bay and find the box pocket. I'm not saying it can't be done, but I am saying that I've snaked wire down through all types of insulation, and foam is the most difficult.

Tue Jan 26, 2010 3:43 pm

good to hear these things, opinions from both sides. i am going to guess that there are different types of cured states for different types of foam.

our situation will likely be include the need to change outlets on interior walls. the siding of the house is stucco that seems to draw water in and get the old paper backing damp. I can see the paper in the garage that has no drywall. My thought was that the foam would be better than a blown in fiber for semi moist conditions, and of course new exterior paint.

Tue Jan 26, 2010 3:51 pm

wgargan wrote:
our situation will likely be include the need to change outlets on interior walls. the siding of the house is stucco that seems to draw water in and get the old paper backing damp. I can see the paper in the garage that has no drywall. My thought was that the foam would be better than a blown in fiber for semi moist conditions, and of course new exterior paint.

That is a distinct possibility. I would be interested to know what you find out if you research this further. Something is missing from the equation if you have moisture being drawn through the stucco. I have never installed stucco, but I would imagine there should be some sort of building paper or vapor barrier between it and the interior wall bay.