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framing and insulation

Hi, I have a bi-level home which is partially below grade. The lower level was gutted and now only has cinderblocks with a couple of windows. The walls were previously paneling and without any insulation. I would like to frame the room and would like advice on the type of studs that should be used (wood or metal). The home was previously impact by flooding but we have since fixed the drainage issues on the outside of the home. However, just in case we should run into problems with flooding in the future, which studs would be beneficial to this room? Also, what type of insulation is recommended for a bi-level home and is a moisture barrier recommended? I feel that if a moisture barrier were to be installed it may trap moisture between the cinderblock and the barrier. Wouldnt this be creating a environment for mold growth? Any advice would be greatly appreciated so we can move forward with renovating appropriately. Thanks :-)

Re: framing and insulation

I would use spray foam insulation for sure and use moisture resistant drywall.

Re: framing and insulation

i would hang 6 mil poly on the cinderblock walls and have it continue under the base plate for the walls. then for the wall framing use PT a base plate with regular KD studs. regular r-13 insulation in the stud bays and you can finish the walls however you wish. whatever you do decide to use for the finished walls, keep the material at least 3/4" above the floor and the base trim can go right down to the floor. that way if the floor ever does get wet or damp it won't be transfered to the wall material be it drywall, paneling, etc.

Re: framing and insulation

You are right about that if the cinder block wall were to leak, moisture would be trapped between the vapor barrier and the cinder block and that could promote mold. But, if you are going to use this space as a living space or use it for laundry, bath etc, you are going to generate humidity. If you don't use a vapor barrier, then that humidity will penetrate into this area and condense, thus promoting mold growth. So in the end, you need the vapor barrier.

Start by painting the cinder block wall with a paint that has a mold inhibitor in it. For studs, use a PT 2x4 for the sill plate. Use regular kiln dried (KD) wood for the studs. But, coat all the wood with a sodium borate and antifreeze solution. You can buy this premixed as a product called Boracare or make your own.

If you make your own, you should do this on a camp stove outdoors, do not do this inside your house. You do not need fresh antifreeze either, used antifreeze will work, but if you use used, do not dilute it further. You can also use fresh premix (50/50) instead of straight since you won't need that much.

Bring up a gallon of used or premix antifreeze up to about 280°F. It will give off vapors so do not breath these. Then add one pound of Boric Acid (roach powder) and 1.5 lbs of Borax (20 mule team). Mix until the powders dissolve completely. When it is cool, you can apply to the studs with a garden sprayer or a paint brush. It will prevent the wood from rotting or growing mold if it gets damp. Do the PT as well as mold will grow on PT lumber.

BTW, there are two more advantages to this solution, its a fire retardant and it is an insecticide that is very effective against ants, roaches and termites.

Or you could just glue foam boards directly to the cinder block wall and then glue the sheetrock or paneling onto the foam.

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