I’ve got a client who wants a finished basement, but doesn’t want any foam products used inside the house for insulation.
Any consensus on what’s the best approach to basement insulation that doesn’t involve rigid foam or sprayed foam?
Steve
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Just thinkin' out loud: Waterproof membrane on the interior walls, sealed well everywhere but the bottom. The bottom drains into an interior french drain to handle any moisture that finds its way in. In front of that, steel studs w/ fiberglass batts & DensArmor, or other paperless or mold-resistant DW. Vent the space between the foundation & interior wall to outside, if possible.
Mike Hennessy
Pittsburgh, PA
Everything fits, until you put glue on it.
A couple of options. Insulate the exterior w/ foam (is that OK w/ them?) or insulate the interior w/ FG batts. Assuming the exterior is well waterproofed, this is often done I think.
maybe take a look at airkrete? I don't know much about it, but it might fit here.
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
Why doesn't he want foam inside the house...? I can't help with your question I'm just wondering why.
She's concerned about off-gassing. I think she's coming around to it though. Fear of mold is worse than fear of off-gassing...
use EPS foam. no offgassing.-------------------------------------
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
Gonna go with XPS behind a stud-wall. Any thoughts on the best way to fasten it to the concrete? In the past I've tacked it up with roofing tins and tapcons. Not looking forward to doing that again. Foamboard adhesive always seems not to hold very well.Also, anyone see any need to space the stud wall away from the foam or can I just slam it up against it?Steve
When doing basements like this, I use 1-5/8" metal studs. I set the tracks first, 2-1/4"" out from the wall (bottom track on 3/4" X 2-1/8" stick of PT, tapconned to the floor). Then I stick 2" foam sheets to the wall with either spray foam or LocTite Hi-Tac adhesive. I then throw a couple of steel studs up temporarily and brace the foam sheet in place. If necessary, I jamb a couple of foam scraps between the stud and the sheet just to hold it in place. (The LocTite works better in spots where you can't brace well 'cause it has a higher initial tack.) Go back a couple of hours later & the "glue" has set up enough that you can go ahead and set the studs permanently. If I want additional insulation, I'll add another 1" foam panel between each stud. Cover the whole mess with DensArmor paperless DW.
(BTW, I was picking up some DensArmor the other day at the local supplier and he gave me a big roll of paperless tape as a sample. Not the usual FG mesh stuff. This stuff looks like really thin felt, but it's FG. Nice stuff! And perfect in situations where you want to avoid paper, like basements.)
I also use up any leftover foam to put a "dot" or two of foam between the center of the studs and the foam panels mounted to the walls -- this firms up the wall nicely by bracing the otherwise flexible studs to the wall at their center points.Mike HennessyPittsburgh, PAEverything fits, until you put glue on it.
A recent flood has me reconsidering basement insulation.
Moisture is a given; right now I'm leaning toward rigid fiberglass panels, spaced off the wall with stucco lath / screen. Let any water that comes through the wall drip down the wall.
I'm also stopping the insulation 6" or so above the floor. Remember, the temperature of the ground is fairly constant, and does not reflect the extremes of winter and summer. That is, you might want R-25 at the top of the wall, but only need R-5 at the base.
By stopping the insulation above the floor, it will not be in contact with a minor flood, such as the one just encountered. The same should be done with the wall sheathing: stop it short of the floor, and let the baseboard cover the gap. Much of the damage in this flood occurred because the remodeler had set his panels snug with the floor, then trimmed the tops to fit the ceiling. 1/2" of water on the floor will wick it's way 4" up the drywall (and 12" up the panelling) in just a few hours.
The steel studs were a godsend in this flood. It's amazing now much water wicked into the stair framing. Where wood must be used, get pressure-treated. Heck, after this, I'd soak the ends in shellac too!
For the baseboard ... consider the plastic stuff, as it will not absorb water. Keep the lengths fairly short - say, about 6ft- to reduce breakage when the time comes to remove it.