Basement Insulation Question

gilbo125

So I'm finishing the basement and sticking to the whole rigid foam, inch of space, walls studs with unfaced batts of fiberglass insulation. My question is what kind of insulation to put up when you're building a wall NOT against the foundation. Say a wall that seperates the finished area from the utilites area (housing my water heater and furnace, etc..). Should this wall have unfaced or faced if any insulation at all. Also, if faced does the facing face the finished area or unfinished area. Also, has anyone had any experience with cutting the facing off for insulation the walls in front of the rigid foam?

So to sum up my questions...
1. What kind of insulation for wall between finished and unfinished area?
2. If faced batts, does the facing go against finished or unfinished area?
3. Anyone cut the facing off of the batts to put up in the walls in front of rigid foam insulation?

Thanks in advance for any feedack!

jklingel

If you are talking about an interior wall, you don't need insulation except to cut noise somewhat, if desired. (Extra layers of sheet rock do better at noise reduction.) On your exterior walls, I would not advise an air gap; you'll get convective currents and really reduce the R value of the wall. I would also not advise fiberglass batts for ANYTHING, esp in a basement. If you use FG, tearing off the facing leaves them wobbly in the walls and you'll have more gaps than normal w/ them; one reason I don't like them. Do a search here, and/or buildingscience.com to help clarify any concerns.

gilbo125

Even no insulation on an interior wall between a finished (warm) room and unfinished (cold) room?

jklingel

Oh. In that case, sure, insulate. I assumed they were both heated rooms when I said "interior". To me, what you have is an exterior wall. Ok. Now we're on the same page. Bottom line: Heat goes to cold, up, down, sideways, doesn't matter. Q = UA (delta T), so if you have a temp differential and don't really want to heat the one side, then insulate and air seal. A one square inch hole will transfer as much water as will diffuse through a whole sheet of sheet rock in a "typical" house scenario. Good luck w/ the project. j

Squeakyhinge

I heard the cold air from the floor should be insulated from the warm, ambient air inside the wall.

federer

why not insulate all teh way around the basement?

jklingel

Squeek: Sorry, I don't follow you. Always insulate between warm and cold.

Gary in WA

And no air space;http://joneakes.com/jons-fixit-database/743

Gary

__________________

Squeakyhinge

Didn't mean to interrupt . Whenever I do that with my friends they call me Mr. Mumbles. I like Squeak better.

I am in the middle of an extremely slow basement finishing job. The next step is framing. I read once on another forum that on the interior walls (should have specified in previous post) need insulated also because the floor can be cold and the room air warm. Does this sound like a tall tale or what? Now I want to find where I read that Now I'm wondering if the baseplate would actually provide plenty of R-value to insulate this minor temp transition. Sorry.

iamrfixit

If both sides of an interior wall is a heated space the wall does not need any insulation. Many times interior walls are insulated to reduce sound transfer though.

It is a good idea to put the thin foam sill sealer between the concrete and the sill plate to keep the wood from direct contact with the concrete floor, not for insulation but so moisture does get to the wood over time.