We have a fieldstone/mortar foundation with a few courses of concrete block. The basement is dry, the stones are sound and painted with waterproofing paint. I am cleaning and re-organizing the area, and when I was vacuuming the sawdust off the walls, I could feel the cold air coming off the wall. I grabbed my laser thermometer and the wall was between 53-55 degrees. All the joist bays at the rim joist are filled with fiberglass insulation. In a few other areas I have put up reflectix roll insulation, slightly overlapped and foil taped at the seams. I am planning on putting up Reflectix on this next wall, taped seams, and stapled up around the joist. Frame 2 x 4's and put up rough pine. I use trim screws on the rough pine in case I need to get access to the wall. Anyone have a different opinion on insulation. I want to avoid foam, where I have fieldstone, in case something needs to be re-pointed down the road. Any thoughts on pink insulation or foam board? The reflectix has only a little over 3 R Value, but it is easy to install and a radiant barrier. Taping it should stop many drafts if i go all the way across. Pink would require framing at 16", where I would otherwise go 24" and run nailer across to secure the pine. I'd like to add either a fan heater down there with hot water coil off the boiler next year or a toe kick heater. The basement is just for shop use and not a living space.
foam board against the stone as a thermal break, then framed with pink, check, some of the pink is available for 24" spacing.
In one section of my basement I put up foam board then installed the studs (2x3 wood) used fiberglass bats that were 11 or 13r, then put up wallboard. Another section that I wasn't going to be able to attach upper support to the sill, I used foam board, then Reflectix, then the studs screwed into the cinderblock wall on top of that (metal studs so only about 3/4-1"), left the air space between the Reflectix and the wallboard. I used an IR gun a couple of weeks ago (during the deep freeze) to see if one section gave me a better barrier than the other. The readings were within 1/2* of each other - at right around the room air temp. So, it doesn't seem to matter if you use the Reflectix and air barrier or the fiberglass bats once you have the rigid foam installed - at least in my application. Oh yeah, I still have some bare concrete block (painted) behind the P61a and that was reading at about 55*
Looks like the 24" is r- 30 and 38 for attic. Might just make sense to go 16" o.c. Foam board sounds good so far.
The reflectix gives me a little more flexibility to get behind the baseboard heat pipe just below the floor joists and I have the gas line and meter in the plane of where I want to have the wall. I may have to box around it or go behind it. That would make less room.
I ended up cutting around the drain line for the washer and to the main drain also. I do have a couple places for the FHW pipes that I didn't have room for foam board so I did just do a layer of Reflectix. Because I know where that area is at, I can see it in the pictures of the metal studs in my earlier post (upper left corner). I did put up foam as close as I could first.
Some interesting information on Reflectix here: Stay Away from Foil-Faced Bubble Wrap Edit: you might also check out Roxul. Lowes in our area carries it. I love working with it as compared to fiberglass.
I've always used reflectix as a radiant barrier and to cover the foam boards because of fire safety recommendations, "Polyurethane and polyisocyanurate foams used in interior applications should be covered with a thermal barrier." Since I knew a lot of the foam board would be exposed for years before I got around to studding out and sheet rocking, that was my main consideration. On the walls I have managed to sheet rock over Reflectix, I left an air gap to allow for the radiant barrier to do its thing. I have two walls that I did regular R-13 insulation over rigid foam and I have a little over 1 wall that has the foam board, reflectix, air gap then sheet rock. Both wall IR out to approximately the same (the reflectix side is a little warmer - as it should be as that room is a little warmer naturally). Am I claiming that Reflectix is the same as R-13? No, I'm not. I'm saying it works well in satisfying my requirements, use and application. Edit - I forgot to state that the R13 insulation in the basement is a bit compressed in the space that I have it so I'm most likely not getting R13 insulation value. But it isn't squashed flat so I would expect at least R7 if not more.
Rmax polyiso foam board is a fire-rate product that provides good r-value for the money as an alternative to Reflectix. I used to use Reflectix extensively but found better alternatives that also didn't advertise deceptively.
