Basement wall stud questions

[Brad54]

Okay, it's not a garage, but I trust the collective opinion here.
I've got a full basement that was never finished, but it was stubbed for a full bathroom. It has walk-out doors and a couple windows. One and a half walls are wood stud, the rest are poured concrete.

I want to start finishing the basement, and that means putting walls and sheetrock against the poured concrete walls.

Is there a reason I can not just lay the 2x4s flat against the poured walls and use a Hilti gun to secure them to the concrete, then secure the sheetrock to it?
Why would I have to have full, traditionally framed walls with a header and a foot plate resting flat on the concrete floor?

I painted the walls when we first moved in--primed, then rolled on paint. The walls were not smooth--lots of small voids, so the coverage isn't 100-percent, but we don't have a moisture problem (other than it not being air conditioned down there--in the summer, it gets stuffy, unless I run the dehumidifier). Do I need to put up a plastic barrier between the concrete and the studs? And I really can't see a reason I'd need to use treated lumber, like we do with the bottom plate for a wall sitting on concrete.

Thoughts?

-Brad

 

[Scott K]

Too many variables for a simple answer.
Are the concrete walls below grade?

Was there any damp proofing of the concrete exterior?

Any moisture producing appliances like a furnace, washer/dryer or a shower?

Adequate ventilation in the basement?

 

[CNGsaves]

Did exactly what you're planning on my old house basement and installed styrofoam panels between the studs (also laid flat) and then sheetrocked.

Be sure you plan for electrical wiring and low voltage (CATV, internet, phone, etc). Shallow boxes can be used (ie 2x4's laid flat), but have to really plan ahead as very llittle room in box. Don't skimp on outlets . . . every 6 ft works.

If there's spot where you plan lots of wire runs (ie stereo system with speaker wire runs all across the house, security CAT 5e/6 runs, server, etc) then I'd install a conduit in that wall to an oversize box or boxes.

Also, what I'd do different is NOT sheetrock the ceiling as it didn't turn out all that well ("had" to have popcorn to hide blemishes), plus it prevents any subsequent wiring runs or maintenance on plumbing. Instead, there are now some nice looking suspended ceiling options.

I'd keep an area in unfinished portion (ie equipment/furnace room) where all the home runs of CATV & phone all centralize so you can have easy access to wires for splitters, punch-down blocks, etc.

 

[Scott H in Wheaton]

I would use pressure treated wood up against the concrete.
Then insulate with foam panels.
Then cover the whole wall with vapor barrier.
Then panel or sheetrock.
Paneling is quicker and easier to change if you have maintenance issue.

x2 on the 'no sheetrock on ceiling'. It just becomes a pain in the *** when you are trying to do almost any home maint. project down there. (plumbing, wiring, running cable)

 

[BD1]

If you are in a cold winter climate, I would go with standard stud wall to allow for insulation. When I did mine I used 2x4's but secured wall for 6 '' of insulation. I was more concerned about ''R'' value.

 

[garboui]

for northern climates the recommended stack up is:

1. Existing concrete wall
2. Foamboard (the pink stuff) sealed top and bottom with acoustical sealane and seams taped.
3. Studs 1/2-1" from foam board
4. Fiberglass insulation
5. Drywall

There is no vapour barrier as the foamboard takes care of this. The nice thing about the gap between the foam board and studs is that you can run cables behind making insulating easier. I have a pdf that explains this construction in great detail.

I will post it if I can find it.

 

[IHI]

From experience and local code we had to follow, any wood in contact with concrete has to be treated..inside or out does not matter.

From experience, every basement we tore apart to re-remodel, everyone, which was almost all of them, framed/insulated in the way you want had cavities chaulked full of black mold.

Air space, air space, air space...you have to give air space so the moisture that can, does, will build up/wick in, etc...has a way to dry out so it's not sitting dormat and allowed to fester. Do yourself, and possibly the next homeowner a huge favor and build standard walls 1" away from your foundation. Go ahead and insulate with UNFACED batts in the 2x4 walls, but make sure nothing comes into contact with the foundation...air space, air space, air space. I cannot stress this enough.

Spent most of my life hearing the old adage "that's the way my dad, grandpa, uncle, etc...did it and they don't have a problem". WEll guess what, the codes we have to abide by now are in place because your dad, grandpa, uncle, etc..."thought" they were doing things right and down the road failures happened be it rotten this or that when being uncovered, mold, inadequate framing for spans/loads, etc...somebody has gotten sick/hurt/killed at some point doing it the "way so and so always did it"...and that is why we are not allowed to do it that way for paying customers. Hopefully none of you have been on the "next homeowner" end of fixing the previous owners good intentions. I know I left an open clause in my contract for "unforeseen circumstances" and the **** we've uncovered over the yrs would blow your mind...made my job harder and sadly for my customer, more expensive through no fault their own other than buying a house worked on by a hack.

P.S. while you might think your losing "a lot" of floor space doing it how I said..in reality your not and it's the right way.

oh, and you don't need any headers, there is no weight in your framing that will bear..that is already taken care of by your foundation, floor trusses, beams...so you don't need headers, you just need to install nailers so you have solid backing for base molding, casings, and crown if you chose.

 

[dirttracker18]

for northern climates the recommended stack up is:

1. Existing concrete wall
2. Foamboard (the pink stuff) sealed top and bottom with acoustical sealane and seams taped.
3. Studs 1/2-1" from foam board
4. Fiberglass insulation
5. Drywall

There is no vapour barrier as the foamboard takes care of this. The nice thing about the gap between the foam board and studs is that you can run cables behind making insulating easier. I have a pdf that explains this construction in great detail.

I will post it if I can find it.

From experience and local code we had to follow, any wood in contact with concrete has to be treated..inside or out does not matter.

From experience, every basement we tore apart to re-remodel, everyone, which was almost all of them, framed/insulated in the way you want had cavities chaulked full of black mold.

Air space, air space, air space...you have to give air space so the moisture that can, does, will build up/wick in, etc...has a way to dry out so it's not sitting dormat and allowed to fester. Do yourself, and possibly the next homeowner a huge favor and build standard walls 1" away from your foundation. Go ahead and insulate with UNFACED batts in the 2x4 walls, but make sure nothing comes into contact with the foundation...air space, air space, air space. I cannot stress this enough.

Spent most of my life hearing the old adage "that's the way my dad, grandpa, uncle, etc...did it and they don't have a problem". WEll guess what, the codes we have to abide by now are in place because your dad, grandpa, uncle, etc..."thought" they were doing things right and down the road failures happened be it rotten this or that when being uncovered, mold, inadequate framing for spans/loads, etc...somebody has gotten sick/hurt/killed at some point doing it the "way so and so always did it"...and that is why we are not allowed to do it that way for paying customers. Hopefully none of you have been on the "next homeowner" end of fixing the previous owners good intentions. I know I left an open clause in my contract for "unforeseen circumstances" and the **** we've uncovered over the yrs would blow your mind...made my job harder and sadly for my customer, more expensive through no fault their own other than buying a house worked on by a hack.

P.S. while you might think your losing "a lot" of floor space doing it how I said..in reality your not and it's the right way.

oh, and you don't need any headers, there is no weight in your framing that will bear..that is already taken care of by your foundation, floor trusses, beams...so you don't need headers, you just need to install nailers so you have solid backing for base molding, casings, and crown if you chose.

The first quote for the reasons in the second quote.

Concrete will allow some moisture through. The wood directly on the concrete will wick up the moisture and will mold.

Do it right and it will stay healthy and be warmer in winter and cooler/less humid in summer.

 

[larry4406]

I work for a high end production home builder in northern va and md. On our finished basements, we stud all perimeter walls using 2x4's held out 1" from the poured concrete foundation. The top plate is fire stopped using a rip of 1/2" OSB.

The stud cavity is filled with R13 Kraft faced insulation, except for the bottom few inches, then covered with drywall.

The bottom gap and rear gap allows the dead space to breathe, so it has been explained to me.

We drywall and smooth finish all our ceilings.

 

[CNGsaves]

Very good advice by the Canada guys if the OP is in cold climate.

Midwest USA climate is very mild, and my old basement was done 20 yrs ago so may indeed be better building methods if concrete has some moisture. That old house had nice dry basement . . . AND . . now is the ex-wife's problem!

Recommend that OP properly size any HVAC ductwork and design so that whole house heats and cools properly. Builders are notorious for skimping on ductwork and taking shortcuts. I'd sure recommend plenty of return air ducts to major spaces upstairs, and plenty big supply ducts. Once that ceiling is all sheetrocked shut, you are stuck with whatever output you get.

OP ought to Update GJ Profile with location so GJer's can give best advice.

 

[Brad54]

I should have said earlier I'm in Georgia. Winter here is 30-40 degrees.

The basement is an "L" shape. The long leg of the "L" (the upright) is 12-foot ceiling. The stairs come down between them, and the short leg of the "L" has standard 8 foot ceiling.

There was a moisture treatment on all the concrete that was below grade--thick black paint-like coating.

My problem is the way the stairs are situated, you walk under them to get from the long leg of the "L" to the short leg, and the pass through has a studded wall area on one side (which will become a closet... I still can't believe they didn't simple add a door to it) and the concrete wall on the other.

In other words, to go from one room (long leg of the "L") to the other (short leg), you pass through a short 3-foot long hallway with a closet door on one side and concrete wall on the other.

The width of the hallway is about a standard width... if I put a 2x4 studded wall, plus sheetrock, plus 1-inch air gap along that concrete wall, that short hallway will be too narrow.

-Brad

 

[nolimits76]

If I understand your problem correctly, a "pony wall" would work. I would want another solution, but it's possible. I assumed your treads were 10" wide and risers are 6" high. Depending on actual dimensions that would change your other height dimensions because of the angle of the stairs.

At least this gives you an idea.

 

[RickP]

In other words, to go from one room (long leg of the "L") to the other (short leg), you pass through a short 3-foot long hallway with a closet door on one side and concrete wall on the other.

The width of the hallway is about a standard width... if I put a 2x4 studded wall, plus sheetrock, plus 1-inch air gap along that concrete wall, that short hallway will be too narrow.

You might be able to use a different wall thickness for the short hallway. It sounds like your ceiling height changes there anyway, so you could have a transition in the hall -- maybe an open doorway or arch to hide the change in wall thickness.

It sounds like you don't need that much insulation in GA. Are you worried about the wall thickness in the rest of the basement? Do you need the space? You could still use studs laid flat, but leave an air gap next to the concrete.

Another option is to build storage closets along the concrete wall -- my neighbor did that and just left the back of the closets unfinished. It worked great because he now has access to the entire concrete wall to check for mold and he has plenty of storage.

 

[garboui]

Here's the article I mentioned in my original post. Its a solid quick read on basement insulating systems and their rationale.
http://www.google.ca/url?sa=t&rct=j...WDhQWRI6I5r8l49bQ&sig2=kAgkwy5hebHSvaYgM_qQ6g

If you have a lot of time to read, here's one put out by the Ontario Gov.
http://www.google.ca/url?sa=t&rct=j...=xk4_58P1jrtuR1Ikb6r4bg&bvm=bv.50768961,d.Yms

 

[RickP]

That's a great article - I'm going to be doing my basement soon. Thanks for the post!

 

[Pat Brady]

I have redone my basement like you are planning. All you have to do is wedge the studs/walls tightly between the (overhead) floor joists and the basement floor. Tack them down. More than likely, the moisture will come up through the floor. So, there isn't much you can do about it other than running a dehumidifier. That should take care of the humid conditions.

 

[SlappyWhite]

If there is a gap between the cement wall and the insulation you will rot the floor joists over time. In winter the bottom of the foundation is warm and humid. The top is cold. The warm air will rise in the gap between the foundation and insulation and will condense on the cold headers and joists. So gap is BAD. Solution is foam against and sealed to the foundation.

Wood studs against the concrete will rot, so foam against the foundation again...

Steel studs conduct too much temp, so they are a bad idea for outside walls.

Batt insulation must have a near perfect seal on the WARM side in winter. A value barrier on the cold side can be bad and cause condensation issue if there is any hole on the warm side. So it is not a good idea to use foam on the outside of batt, this goes against my first point....

So, foam board against the wall, strap, call it a day. Or build your stud wall with a gap and spray foam the gap and between the studs.

 

[bop_pa]

I have done a few basements and built my house. My vote would be traditional stick built and skip the method you mentioned. I just think it is the same amount of work without any real benefit. However, as an alternative check this wall system out from Owings. Comes as a full insulated wall panel for easy install: http://basements.owenscorning.com/bfs/products/#

 

[IHI]

I have done a few basements and built my house. My vote would be traditional stick built and skip the method you mentioned. I just think it is the same amount of work without any real benefit. However, as an alternative check this wall system out from Owings. Comes as a full insulated wall panel for easy install: http://basements.owenscorning.com/bfs/products/#

Unless OC has changed yrs ago you had to be an authorized dealer/installer to get your hands on their basement system. I looked into it and the numbers blew my mind, it's nothing a small company like I had even had a chance to buy into. The royalties, the amount needing purchased per month, their sales expectations was ridiculous to say the least, it would have to be a large company with an extremely strong sales staff and ways to finance to close enough of the bathroom restroom looking walls to make it work the way OC wants it too.

 

[gungatim]

If you are thinking about the half concrete walls, here is what I did: all cement walls have 1x2 nailed into the concrete. The half walls I did the same, but stopped the studs at the end of the concrete. I then put a 4" or so strip of oak plywood horizontally to make a shelf at the transition between the cement knee wall and the traditional stud wall (cement is like 8" and the stud wall is around 4"). That way I have a nice little shelf for knick-knacks (or beer bottles or whatever) and didn't have to re-do the stud wall that was already sheetrocked. The edge of the plywood just has some solid oak nailed on to finish the edge. Here's a pic during the re-model before the edging was added.

 

[avc8130]

When I finished my basement in my old house I did it myself spacing metal studs 1" off the concrete walls and insulating.

I learned a few things:

1. I FAILED inspection.
You MUST provide fire stops. Look up your code. You will need something solid at the top of the wall to cover that 1" and create a "ceiling" in that space. You will also probably need fire stops along the course of the wall at a certain interval. The theory is that a fire could start behind the wall and run its course VERY quickly before actually being noticed.

2. The metal studs were a mistake. Sure, they were fast and cheap...but I could see EVERY one of them through the sheetrock once the weather changed.

I have no clue what the "proper" method of insulating is. I have read every possibly scenario. I have seen every possible scenario. In MY old basement I put faced insulation with the face behind the sheetrock. In my NEW basement, that a "professional" installed, they used vapor barrier behind the sheetrock in front of the insulation.

Good luck.

ac

 

[gregcr]

I did similar to garboui, with a little twist.

2in pink foam board directly against the foundation wall.
Used 1" furring strips at the seams of the foam board, kept 2" off the floor.
Used tapcons through the furring into the wall. Drywall over on the furring strips.
It was suggested in Fine Homebuilding.

I routed chases in the foam for electrical and covered all electrical with sheetmetal.

Between the foam and the 1" airspace it made code for insulation requirement.