[Chemist1961]

I just bought enough NEW 3 5/8" steel studs and track for the entire basement at a steal form Habitat for Humanity.
I plan to frame and insulate the outer walls only, within 6 weeks to get an energy rebate.
Several questions,
When I space away from the wall, is there a way to use more than R 13.5 fibreglass insul in , not compressed of course?
Can I use R20 and let it hand out the back without collapsing, or is there a way to support it to keep from sagging or is spray foam or rigid in behind my only other option.
Second, if I spray foam, then obviously no air gap, but can I spray over a wall with a fine crack / leak which is caused by bad drainage outside... in a window well. The drainage is being improved as I plan to excavate the outer wall and clogged window well to seal at the same time.
Any other pointers for lapping corners , etc with steel studding would be appreciated.

 

[Ron6519]

When I used steel studs for the basement I flipped every other metal stud around so the "U" shaped recess held the insulation in place on one side, which was more then enough. The batt insulation is pretty rigid.
You could do the same with, say R-19. You just put 3 1/2" into the channel and let the rest stick out the back. The studs are spaced closer then 16" on center, so the sheetrock is a little more of a pain to install, But putting batt insulation in steel studs is a challange, especially if you don't want it leaning against the wall.
By lapping the corner, do you mean having a screwing surface in the corner for the drywall? If so, you just frame it out just like you would with wood studs.
Ron

 

[Chemist1961]

Thanks Ron, actually meant how do I frame the tracks at ceiling and floor for inside and outside corners, just a butt joint or do I knotch and interlace them. I am debating fastening to the floor with drill and tapcons or a ramset hammer. Have both hammer drills and single fire Remington Ramset tool

I am also debating insullation materials, was just quoted $3.45 per squure foot for 4.5" foam at R24, including rim joist although I have resealed the rim joist and sole plates myself.
Any comments from anybody?

 

[AtlanticWBConst.]

Insulation for steel framing is different from residential R-13 made for 2x4 studs. There is a a difference of 1/2" in the stud bays. (wood studs: 1-1/2" x 3-1/2" / Steel studs: 1-1/4" x 3-5/8")

If you locate and purchase commercial fiberglass insulation (Usually sold at Drywall type supply houses), you will find wider insulation (unfaced), for the 1-1/4" steel stud bay-width.
You may have to install a poly vapor barrier over that, facing the warm side.

 

[ccarlisle]

Steel studs are a no-no in basements. Will rust and will rust screws within 5 years. Transmit cold from behind...

And they will affect the type of electrical wiring you are allowed to use.
:yes:

 

[Chemist1961]

Has anyone got any feedback, good or bad on Icynene and its enviro freinldy claims. Arethere othere "non chemical" type foams ?

 

[ccarlisle]

Spray foam is the cat's meow in terms of insluating materials that double as air barriers and when I redo my basement, tahat's what I'm getting. Now I don't know if it'll be Icynene or another - but it'll be a PU foam of one kind or another. Go to their website and see the advantages...

Only drawback is cost but then the higher the cost the higher the payback. But that's all you'll need on the wall. A few inches of PU foam and no more air leaks.

Look I don't have any experience with it, so can't quote numbers, or what. Mike Holmes uses BASF's WALLTITE and it's the same I think. But not everyone has bottomless pockets like he does and not everyone has a virgin canvas to play with - but on the other hand if money buys the best, WALLTITE it is...

 

[II Weeks]

Steel studs are a no-no in basements. Will rust and will rust screws within 5 years. Transmit cold from behind...
.

If done wrong, this statements right.

We use styrofoam on the walls and then 2X2 metal studs in front that. let the track sit on top of a double layer of rolled pink foam insulation. No rust and termites and other vermin and mold dont like the metal studs either. Wood in basements is a no-no.

We also use green board for the bottom perimeter all around the regular white on top and ceilings

Not sure where you live but R20 for a basement is overkill IMO. 2" foam is good enough with R19 in the floor joist bays at least 2' into the room all around.

 

[Chemist1961]

Thanks II W and CC and all. I live between Toronto and Detroit . Here's the thing, if I insulate to R23 I get a $2750 eco energy rebate, if I do only R13 I get $1350. So the 140 studs and 320 ' of track cost me $200 for a 1100 foot basement. Insullation will be the large material cost. I'll either use 2" rigid foam plus batt or spray foam. If I spray foam, i'll break even or close after additional 15% tax credit, If I do batts and foam board to R23, my drywall becomes free...
CC I appreciate your concern on the steel with moisture and rust. I see alot of steel in better quality homes in our area. I will be insulating below and behind and run a dehumidifier in the basement as well. Just not sure about Icynene. I amstill ab ibit aprehensive about flamables with toxic fumes in my basement. I think I will use Roxul batts for steel studs.

 

[ccarlisle]

Chemist:

I am sure you probably do see steel studs in better built homes in your area...I do too, but the difference is that the insulation cavity behind the studs on exterior walls in basement has been dealt with by foam or by some means that reduces air movement and creates a thermal break between the surfaces. Metal studs are most commonly used by contractors who think they can save scratch.

And whoever said wood in a basement is a no-no is also uninformed. Humidity in a basement is a no-no, not wood. Using his reasoning, most joists, studs and floor covering would be no-no's too. If wood were 'banned', the so wood gyproc, so would paper, so would paint. It's the humidity that has to be controlled - but again even if it is, steel studs in a basement is a no-no unless the insulation has been upgraded.