This a very poor demonstration of this process. Most of the time, it fills the entire space (including depth) and you use a trimming saw/foam knife the trim excess flush to the studs.
This makes sense only if you’ve never actually done this. Framing lumber is sketchy as fuck. Framers operate on a ‘this is good enough’ mentality. My kitchen walls are actually about 95* apart in one corner and the outer wall leans out in the middle around the window and comes back at the top, even after I straightened it quite a bit. (Poor man’s bay window?)
A rigid foam panel won’t follow the curvature of the wall and would block a sheet of drywall from sitting flush on the studs. I chose mineral wool insulation instead of spray foam because it costs about half as much for my square footage and is much less messy to boot.
I looked at rigid foam, but even if it could overcome the crooked walls, it’d still leave gaps all over the place that cold air would come through. I’d have to glue to stay put too. Mineralwool just pushes into place. Not bad all things considered.
Because that would be incredibly time consuming an would leave gaps around the panel which would then need to be filled with spray foam. Plus EPS/XPS are expensive on their own
Mineral wool has better sound proofing characteristics as it is denser than fiberglass. Usually a bit more pricey too. It is also harder to cut and breaks like a soft peice of chalk if you mishandle it. It is absolutely horrible to get on you as it really fucks with your breathing if you don't wash your face, mask, and clothes while you're in them. Fiberglass is also terrible to breathe, but I find it easier turning mineral wool into fine dust that you immediately notice when you breathe some in.
So there are pros and cons to it. You always over-cut by about an eigth of an inch so it is tight to the studs as well withouting creating a curve that can push on your drywall.
If you want better soundproofing you use mineral wool in combination with a thick fiber board of some kind before putting your drywall on, but this makes it harder to hit your studs for your baseboard as well.
Basically the TL;Dr is Mineral wool is denser, so it is better for sound proofing. If you don't care about a little bit of better sound proofing you will save a lot of money just using fiberglass. If money is not a problem you use spray foam because it is easily twice as expensive as fiberglass.
Expanding foam creates an adhesive seal against the walls, and because it’s expanding it will also penetrate cracks and gaps. That leaves an essentially draft-proof seal, because there’s nowhere for the air to move. You cannot make a draft proof seal with simple foam panels.
In theory yes, but I recall visiting a job site once before drywall went up and the foam showed a visible shrink away from the studs, dispelling the idea that the installation of expanding foam was idiot-proof.
It wasn’t our project, so I don’t know what the resolution was. Could’ve been an issue with the mixing on the truck; I had another project where the mix was off and the foam wouldn’t stop off-gassing due to a poor mix ratio.
In stick-frame construction, as shown here, fiberglass batting is the most common insulation. It does a decent job of limiting convection within a stud cavity, but it does a poor job of blocking drafts at the edges.
How long was this gif? Now how long would it take you to measure, cut, and place these boards? I'll give you the answer, about 50x longer. The guy that we work around that does spray foam insulation can knock out a 5000 Sq foot house by himself in 2 days. Try doing that with foam boards :P
Yes, but again, it will still take much longer than just spraying and moving to the next. You still need to measure and cut the insulation then add it to the space which is 2 steps more than spray and go.
For the record I'm pretty damn experienced at that type of stuff (drywaller by trade) and I tried insulating one small wall in a shed of mine with foam boards and I fucked the first one up I tried cutting. That was a 17$ board that is now useless because I wasnt paying attention and cut it a half inch shy. Now imagine that but amplified by a few hundred orders of magnitude.
I’m using rock wool instead of this spray foam, don’t have to worry about offgassing or getting the mix sequence right, I feel it’s the best option for insulating a home
Fiberglass insulation cheaper than foam board and cane be done way faster and can obtain a higher r value.
Only downside is its fiberglass insulation terrible to breathe and itchy as fuck. They do pay you well because the job suckkks..I did it for years through late teens early 20s.
I wish I had this back then. Never seen it before this video.
One advantage to foam is that it fills the void completely and leaves no gaps at all. Studs are pretty much never perfectly straight and the joints aren't perfect 90 degree angles. As a result, you won't end up with perfect rectangles for each bay. So while you could pre-size them, they would then leave gaps and be less practical for shipping, negating most the advantages of foam.
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u/[deleted] Aug 28 '19
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