I’m planning to have my first house insulated with spray foam but I haven’t used this product before. My friend recommended this spray foam company that I can hire, though I’m not quite unfamiliar with this kind of insulation. Has anyone experienced using this type of insulation? TIA!
Yes i have.
I work for a luxury home builder.
Spray foam insulation is good for sealing the wall stud pockets but be careful when there is two or more studs clad together. They can't be foamed in between. Make sure that either the drywallers or someone else uses acoustical sealant on those joints and the bottom and top plates or there will be air leakage.
As well our last house had 5" thick foam in the walls and for some reason cell phone reception went out the window after it was done.
I work for a luxury home builder.
Spray foam insulation is good for sealing the wall stud pockets but be careful when there is two or more studs clad together. They can't be foamed in between. Make sure that either the drywallers or someone else uses acoustical sealant on those joints and the bottom and top plates or there will be air leakage.
As well our last house had 5" thick foam in the walls and for some reason cell phone reception went out the window after it was done.
Kamron Mason,
This is diyAudio. The construction tips refers to building audio equipment. That said, I am a consultant in a related field. Are you speaking of expanding foam or blown-in insulation? Post a link to the product in question.
This is diyAudio. The construction tips refers to building audio equipment. That said, I am a consultant in a related field. Are you speaking of expanding foam or blown-in insulation? Post a link to the product in question.
Many people here on older houses make two holes on the outside and inject this type of expanding foam, between the two walls. When the foam reaches the other upper hole it is filled. Of course there can be no old insulation (styrofoam / glass fibre) between the two walls. I did spray it on my roof and it works.
+1 here.....it’s about twice the initial cost but it’ll pay it back, our power bills are under $100 a month with electric heat/AC, our neighbors with similar size houses but fiberglass insulation are paying $300+ per month.
As I understand it, these days eliminating thermal bridging and protecting the structure are high priorities.
Wood studs represent effective thermal bridges.
Insulate between the studs if need be but first wrap the exterior stud walls in taped (sealed) poly-iso or some such.
YouTube
And to bring this back to audio... while you're at it give some consideration to sound isolation. Reducing the ambient sound level in the house -- and particularly the listening room -- will enhance your enjoyment of the music. That's the prime directive after all, eh.
Wood studs represent effective thermal bridges.
Insulate between the studs if need be but first wrap the exterior stud walls in taped (sealed) poly-iso or some such.
YouTube
And to bring this back to audio... while you're at it give some consideration to sound isolation. Reducing the ambient sound level in the house -- and particularly the listening room -- will enhance your enjoyment of the music. That's the prime directive after all, eh.
I would not use it at home other then small applications from a can.
Most foams absorb moisture, lock water in and get wetter and wetter over time and lose their insulation properties. Also many closed cell variants, although less.
The real closed cell foams will not get wet, but are a vapor barrier itself which can lock moisture in the surface it is applied to and can also create moisture problems.
Styrofoam is one of the few foams that can dry out well and is often a better choice then it might look at first glance.
Mold loves dark moist places and can be very harmful for our health.
In dry climates you might get away with this but termites and other unforeseen problems (electric/plumbing) can get a real problem.
Especially in combination with wood you have to be extra careful as it will rot.
Just to get some ideas of what can go wrong: YouTube
Do your own proper research as the spray foam company will not have to live in your home or sell it later. Doing this wrong can get very costly.
Most foams absorb moisture, lock water in and get wetter and wetter over time and lose their insulation properties. Also many closed cell variants, although less.
The real closed cell foams will not get wet, but are a vapor barrier itself which can lock moisture in the surface it is applied to and can also create moisture problems.
Styrofoam is one of the few foams that can dry out well and is often a better choice then it might look at first glance.
Mold loves dark moist places and can be very harmful for our health.
In dry climates you might get away with this but termites and other unforeseen problems (electric/plumbing) can get a real problem.
Especially in combination with wood you have to be extra careful as it will rot.
Just to get some ideas of what can go wrong: YouTube
Do your own proper research as the spray foam company will not have to live in your home or sell it later. Doing this wrong can get very costly.
> there can be no old insulation (... glass fibre) between the two walls.
There "can".
I have a house built in the first days of Fiberglass. They had an "economy" thickness, which was admittedly better than nothing (I have lived with nothing). 2" thick in full 4" stud spaces. A decade later they drilled the holes and pumped foam. As far as I can tell the fiberglass essentially collapses under the pressure of the foam.
There "can".
I have a house built in the first days of Fiberglass. They had an "economy" thickness, which was admittedly better than nothing (I have lived with nothing). 2" thick in full 4" stud spaces. A decade later they drilled the holes and pumped foam. As far as I can tell the fiberglass essentially collapses under the pressure of the foam.
In my particular case I used closed cell foam between the rafters and roof decking for a few reasons, 1) it’s waterproof..... i weighed the consequences and if there were to be a leak I’d rather it be contained than drop into the house. 2) it’s structural......the closed cell foam adds a considerable amount of strength to the structure,( think urethane glue!) 3) there’s more R factor per inch of foam compared to open cell.
Closed is about a third more cost than open cell but in my case worth it for the roof.
Open cell on the walls and floor.
It cost almost $10k to do a 1500 sq’ home,( fiberglass quotes came in just under $6k)
As far as mold goes be sure to hire a reputable contractor that will not leave voids behind the foam, that is the major cause of mold.
The foam insulation itself does not grow mold, in fact the the thermal reaction kills any pre existing mold, I also sprayed the entire inside structure with a borate solution (timbor in my case), also sprayed the foam itself before drywall. Borate is a very effective mold killer (Insects also) and protection lasts for decades.
Code here required a vapor barrier (tyvek etc) envelope over the sheathing and from what I can tell my house is as tight as a crabs behind (and that’s water tight!)
After hurricane Michael I was involved in the demolition of many beach front homes that had foam insulation.....none had any mold, even ones that were exposed to water damage and sat for months. Now everything else molded (drywall,carpeting, interior woodwork, etc) but not the foam.....I was quite amazed and happy (as mold was also one of my concerns).
Do it right and you’ll be glad you did.
Bob
Edit.....be sure to all plumbing and electrical rough in complete before spray foam.....for obvious reasons!
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Thanks Bob! Great info, very thorough. I'm one of the $300 in the summer electric bills. We don't even run it cold. About the same size house but 70s vintage and leaky as a sieve. We're about 250 miles farther south, but I don't think it's much hotter here.
My current house has foil/Mylar covered urethane foam sheets for sheathing on the outside of the studs, under the siding.
Part of the magic is the glasses that are trapped within the foam, however, it will eventually outgas and the efficiency is then reduced.
I had an 1896 Victorian, and the city kept calling, asking if I wanted some free blown in insulation. They wanted to cut holes in the perfect, original cedar siding to do that, I told them that was a bad idea. The next owner bought into it, house now has cracking siding, holes where some of the pine plugs had fallen out...
Part of the magic is the glasses that are trapped within the foam, however, it will eventually outgas and the efficiency is then reduced.
I had an 1896 Victorian, and the city kept calling, asking if I wanted some free blown in insulation. They wanted to cut holes in the perfect, original cedar siding to do that, I told them that was a bad idea. The next owner bought into it, house now has cracking siding, holes where some of the pine plugs had fallen out...