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Tina, I build with mostly block basements and it is very cold here in the winter. Assuming you have waterproofed it properly on the outside, my favorite method is to use 2×2’s to stud the wall out. I lay on a very generous bead of construction adhesive on the back of the 2×2 and gun it to the wall with an air nailer.The adhesive will spread out and basically isolate the wood from the block. Then I cut 14 1/2″ wide strips out of 1″ styrofoam and glue that tightly next to the 2×2 I just installed. Then install another 2×2 next to the foam and repeat the process. What I like about this method is that it is very fast and makes an airtight seal against the wall. The surface of the wall is insulated and warm, so you don’t have to worry about any condensation forming on the cold concrete as you would if you were dealing with a poured basement wall. You can apply a vapor barrier if you want over the 2×2’s and then apply your wall sheeting material. I have been doing this for 25 years and I’ve never had any problem using this method.
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Tina, I build with mostly block basements and it is very cold here in the winter. Assuming you have waterproofed it properly on the outside, my favorite method is to use 2x2's to stud the wall out. I lay on a very generous bead of construction adhesive on the back of the 2x2 and gun it to the wall with an air nailer.The adhesive will spread out and basically isolate the wood from the block. Then I cut 14 1/2" wide strips out of 1" styrofoam and glue that tightly next to the 2x2 I just installed. Then install another 2x2 next to the foam and repeat the process. What I like about this method is that it is very fast and makes an airtight seal against the wall. The surface of the wall is insulated and warm, so you don't have to worry about any condensation forming on the cold concrete as you would if you were dealing with a poured basement wall. You can apply a vapor barrier if you want over the 2x2's and then apply your wall sheeting material. I have been doing this for 25 years and I've never had any problem using this method.
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Do you use treated material for your studs?
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No, Just SPF If you have a nice dry wall there are no problems. As I said, the glue isolates the wood from the block anyway.
*The problem isn't just rot, but termites as well. having spent too many hours rebuilding my basement walls because they had been eaten up, I have to vote for pressure treated framing there. If termites are going to get in they're more likely to start there. When I rebuilt mine I framed it all out with treated lumber. I sleep better at night.
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I did almost the same thing with my basement walls, but I used 2x3 studs glued flat to the block wall on 24-inch centers, with 1+1/2 inch foam boards (not just 1 inch) so the space was completely flled, then sheetrock over that with the joints vertical, falling on every other stud. It's never happened (yet) but in case we ever get water in the basement I kept the sheetrock about 1/2 inch from touching the floor. I had also painted the block walls with two coats of the UGL Drylok paint, but I'm not really convinced that stuff is any good. Since our basement is basically quite dry to begin with I didn't go overboard with moisture protection.
The Dow foam boards I got were actually 24 inches wide, so I had to zip them through my table saw to make them narrow enough to squeeze tightly between the studs. It's too late now, but I probably should have used PT lumber for the studs, and I will for the remainder of the basement that isn't done yet. I did consider putting a plastic vapor barrier just behind the sheetrock, but I thought that might just end up trapping moisture inside the walls. This is just a workshop, so I didn't tape the joints either, so hopefully it can breathe enough through the joints and top and bottom to get rid of any moisture that might get through the block walls.
There's no wiring in these walls. For my workshop, I've put all the lights and power outlets in the ceiling, leaving the walls entirely free for peg-board stuff and shelves to go wherever they want to go. It wasn't my own original idea to put the power outlets overhead (I read it somewhere) but it was an excellent choice.
Jay
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Carlos, We don't have termites here so I'm not familiar with those problems. How does a termite get into a basement stud wall that is not touching any other wood on the outside??? Just curious....
*Termites make their way in through the tiniest of cracks. There is always some kind of crack between the foundation walls and the poured concret floor. They live underground and extend mud tunnels into your hoouse until they find wood they can eat. From there they just keep eating away from the inside of your lumber, taking cellulose back to the colony. There's also a lot of concern lately over the abilty to tunnel through foam and use the foam to gain access to other parts of your house.
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TinaG. DOW's Styrofoam WALLMATE is still manufactured by DOW.It is available in 1-1/2 and 2-inch thicknesses.
G. LaLonde. Would it not be less labor intensive and less material costly to use the WALLMATE system?
You say, "the surface of the wall is insulated and warm, so you don't have to worry about any condensation forming on the cold concrete as you would if you were dealing with a poured basement wall. You can apply a vapor barrier if you want over the 2x2's"
If I attach rigid foam board insulation (RFBI) to the poured concrete wall--as you have to the CMU wall, I need not worry about condensation forming, do I?
If the Stryofoam is already a vapor diffusion retarder-barrier-why would one want to install a another vapor barrier? GeneL.
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Gene, I personally don't like to rely on nails to hold anything to concrete products. I prefer adhesive. I use a Bostitch gun with the thin hardened nails and they really only hold the wood until the adhesive drys. Personal preference I guess.
As for the poured wall. I have never in my building career seen a poured wall that was straight enough to directly apply framing material to the wall. They are wavy in and out and almost always bulge out at the bottom and at form joints. Everyone I know frames a stud wall out from the poured wall because of this problem. This approach often leads to condensation problems on the concrete behind the studwall. If you could find a decent poured wall, you could certainly use the same technique.
As for your last point. I agree with you. I think it is unnecessary. For some reason, it seems that hardwood paneling manufacturers insist on you doing this. I never use one myself.
*Tina:G. Lalonde's method sounds fine. Just remember that if you wish to get full insulating value out of that wall then make sure to insulate at the top of the wall where the floor joists connect to the Rim joist. You can cut the same rigid insulation board to fit in between the floor joists. I've seen many homes w/ basement tops that stick out of the ground w/ no insulation in that part of construction.This is probably redundant but remember the drain tile at the exterior footing location.OK
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I don't fasten to the walls except in a stairwell where space is at a premium. unless the walls stay dry & have no condensation problem ( how do you know the downspouts will work in the future? Maintence is not usalllly quick on them)I've seen to many glued & fastened systems give up from the moisture.
I come out an inch and set a treated sole plate & frrame the rest with spf. I may be doing a bathroom in a basement with steel studs in the near future. It's gaining popularity in this area & does give for a straighter wall. Termites don't eat them either.
*I don't fasten to the walls except in a stairwell where space is at a premium. unless the walls stay dry & have no condensation problem ( how do you know the downspouts will work in the future? Maintence is not usalllly quick on them)I've seen to many glued & fastened systems give up from the moisture.I come out an inch and set a treated sole plate & frrame the rest with spf. Even if the walls leak, the insulation should be far enough away to stay dry. I may be doing a bathroom in a basement with steel studs in the near future. It's gaining popularity in this area & does give for a straighter wall. Termites don't eat them either.Using full 2x4 studs also allows for fiberglass insulation, full size electric boxes and blumbing runs.
*Cracks as thin as 1/32", I've heard, in the wall, floor or slab. And the basement framing can make a yummy stepping stone to the sill and house framing. Because the basement is finished, you can't see any of this happening. Evil, huh?
*I'm hoping to save some time, money and precious space by putting up a continuous layer of XPS (that Dow pink stuff) or polyiso with the joints foamed, then Tapcon screw 1x4 furring over the foam into the block wall. I'll hang drywall from the furring and spaced from the floor, maybe a cabinet or two. Wiring will be run in baseboard-level surface conduit -- Wire Mold has some attractive low-profile ones now for individual THHN/THHW. Baseboard will provide an easy throwaway layer below the drywall if the basement should flood to several inches. I hope that if the wall should leak, the water will run out the bottom of the foam sheets and under the drywall so I know about it. No wood will touch the slab. I am going to try to retain reasonably easy access with acoustical tile to the sill area for occasional termite inspection.This is, uh, an uninspected situation -- my tax assessment is going up plenty as it is; so I'm building the wall with the electrical exposed to try to avoid a dreaded rip-it-out order from the inspector someday down the line. Everything will be done to code, of course...BTW, I highly recommend GFCI's in the basement, as everyone notes it is not uncommon for water to find its way in the basement. For a workshop, wallcovering tougher than drywall but nonflammable would be great.
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This may sound way too basic for you pros, but how exactly SHOULD concrete block basement walls be finished, in a cold climate, where the room would be used as workshop (i.e. not bedroom or family room or anything fancy like that). For example, starting with the concrete block that has been treated on outside (where it contacts earth). The treatment (and here comes a very technical description) was some black stuff they painted on with rollers. I've read all the stuff about vapor/moisture barriers, etc., but still can't figure out the best basic way to finish, including insulation. (By the way, looked for that styrofoam board stuff (Wallmate?) but their (Styrofoam's) website doesn't include it...is it still available or has it become something else?)