HOHN

Guys, I need some advice on how to move forward with finishing my basement.


The house is fairly new (2005) and the previous owner bought it from the builder. The PO also started on finishing the basement.

The basement is a deep one, with about 11 feet from slab to the ceiling joists.


The PO started framing out the basement, and the plan he had seems workable.

The problem is that he didn't finish the concrete walls or do ANY kind of prep before he got happy with the studding. So I have a LOT of studs in place, over a bare concrete wall. This basement is huge (about 2K sq ft) so ripping all this out is a major project.

I've been told that there is supposed to be some kind of moisture barrier between the concrete walls and the studs. There is currently none, and I don't think I could slip some 6mil sheet behind the current studs and seal it up. A moisture barrier that isn't airtight isn't a moisture barrier-- it's a moisture obstacle.


Anyway, sorry to ramble. I'd love to hear any tip or tricks from someone with some carpentry experience on neat ideas for basement finishing...

Thanks!
Justin

ntnbolt1

I wouldn't worry about it. Are there any signs of water or moisture on the floor or walls normally? It is best to just let the walls naturally breath whatever moisture is in the basement unless there are beads of water on the concrete then you have whole other problem. I would definitely insulate though. If the PO did all that framming already you have saved a pretty good chunk of change.

Bruce

wyododge

^^^^^x2

If you don't see any moisture it has had plenty of time to develop. So you are probably ok. But definitely insulate.

If you are really concerned, get some dry-lock and spray it on. When you get to a stud tap a shim between the stud and the concrete to separate them and spray behind the stud.

If you are really really worried about it. After you spray. Insulate with Styrofoam (not fiberglass) or have a spray foam contractor come in and foam the walls in. Cover your framing with 4 mil plastic, then drywall with paperless drywall (no mold).

If it were my basement, and it was kinda the same. I sprayed drylock, insulated with fiberglass (no paper) put clear plastic over the framing (vapor barrier) and used paperless drywall.

Honestly, you will be fine with insulating with non-vapor barrier fiberglass, and covering your framing with 4 mil clear plastic, then drywall. This is how 90% of the basements we finish are completed. The other 10% have exterior drainage problems which is a whole other bag of hammers.

HTH, let us know how it turns out and shoot some pics.

HOHN

This basement actually doesn't seem to have any moisture issues. Last year when this area saw a 500-year flood, my basement was bone dry.

I'm liking the idea of free batts (no backing) an 4mil or 6 mil over them. I'd prefer styrofoam or some other kind of isulation, but it seems like a hassle to cut it for studs-- I've only seen wide sheets, nothing friendly for stud spacing.

I love the spray foam, but it doesn't make much sense to me a in a basement where drafts and wind aren't problems, and the below grade temps are 59F almost all the time. Above grade, I'd def go with spray foam. A friend had his done and it was awesome.

I'll try to shoot some pics and tell me what you think.

Thanks!

Justin

Colo_River_Ram

The best way to check for moisture is to get a square of clear plastic(that will fit between the studs) and duct tape all of the edges to the wall.. If there is any moisture present it will condensate on the inside of the plastic..(leave it on for a couple of weeks)

I used the sheet foam in my shop there is several varieties of it, white - Styrofoam (is expanded) and the blue or red (DOW brand) is extruded, it has a longer life span than the Styrofoam and has a better R value as well. It is easy to work with and does not require any scratching.. You can score then snap it to width or run it through a table saw then wedge it in between the studs.. Use the new mildew resistance sheet rock and make sure it did not come form China..

Have you looked at the outside of the basement walls? anything built that new should have been coated on the outside (depending on the local ordinances) look a little below surface as they normally stop coating a few inches below grade.

While your in the design mode check out the Rustoleum brand garage floor coatings it is a long lasting water-borne polyurethane system and it does not stink up the place like oil base does.. It even has multi-colored sprinklers for topping..

Hope this helps

newfy

Coat the wall with drylock,
insulate the studding,
rock with greenboard.

Bark

My experience: I received some free blue styrofoam that I did part of our basement with. Because I am cheap, I did the rest w fiberglass. Put clear plastic vapor barrier over it. Never got around to sheetrocking it but after some years I noticed that the fiberglass area got mold between the plastic and the fiberglass and the styrofoam area did not. Dont know why. Wound up replacing the fiberglass with profesional spray foam.

mopar-or-no-car

Its ok that there is no poly behind the studs, vapor barrier goes on the warm side, between the studs and drywall.It is best to have a bit of a gap between the studs and the concrete becuse you don't want wood touching concrete. The spray foam is a great way to insulate all though I think it is alot more money. It works like a vapor barrier if sprayed behind the stud up against the concrete and between the studs the wall should always stay dry and warm.

patdaly

Hohn, you may want to check with the builder, when we did ours in 2004, they sprayed the stickiest goop I have ever seen on the outside of the basement and then insulated it. They call it the 100 year wall.

No way for anything to get through that sucker!

electrifried

Where in the county are you? Some areas are more prone to water seepage. I would not try this in Armuth acres. On Clifty hill would be OK this way. Any where near the Walesboro plant would seep water. My house is on top of a clay hill and water runs thru the basement to a floor drain. A 2005 house in Bartholomew co will have to have had some waterproofing. To sell it to you, it would probably have an inspection and without a barrier you would have been told to use only treated lumber in contact with unsealed concrete when you finished it.

Redleg

Something to think about for sealing up the seems against the studs might be either Log Jam or Perma *****. It's acrylic base and is elastic when cured. It's what they use to seal the joints in log homes. It also bonds to concrete. I've used it on both log siding and stonework, and where the stone buts up the the wood siding. It keeps moisture out, but is designed to allow the subsurface to breath. Doesn't crack with expansion. It comes in a bucket or in tubes.

dfranks

You must use poly, use it on the warm side of the wall (between the drywall and wood studs)

Poly is not designed to stop seeping water it is designed as a "vapor barrier" which is usually caused when warm air meets cold/cool air as in the case of your basement. This is designed to the fasteners from "flashing through" as well as destroying your paint and drywall finish in the process, this normally takes place overtime but can speed up substantially faster if you use a humidifier.

As far as waterproofing your foundation walls, maybe check with the local building codes or with the builder themselves, I know where I live that waterproofing of foundation walls below grade a minimum of 7' followed by sm or weeping tile fastened over to stop frost, is code.

I have 20 years in the drywall and eifs industry

dfranks

As far as your studs go , leave at least 1" of air space between the studs and concrete. You should "clip" your studs to the concrete so as not to have the guitar string syndrome. Use a 2X4 around 6" long and fasten with a shotgun(hilti) at the mid point of the height of the wall. Make sure to use "sill gasket" between the clip and the foundation walls. This isolates the moisture in the concrete from the stud/s.

Do not use treated lumber indoors as it is treated with a pesticide that is known to cause cancer in humans. as well as make you pretty sick in the process.

cougar

I would make a reinforced concrete vault out of at least part of it. You never know when you might need a safe place to sleep some night.

staarma

After 4 years the concrete has probably sweat all it's going to. I don't think you have to worry about anything else. Any kind of vapor barrier between the inside warm air and the concrete would be sufficient if you're worried about condensation.