Hello all, Im a little confused about rim joist insulation as my house is a little older. When looking at a house where the foundation goes up to the rim joist it makes sense to insulate with ridged foam and great stuff as opposed to sticking fiberglass in the joist However,my house is built like this. Foundation, sill plate, 4 feet of studs , rim joist, then subfloor. Does it make sense to place ridged foam in the rim joist in this situation? To me it doesn't. Should the area between the studs be insulated as well? Stucco house if it matters. Thanks

Here is a link for a picture of what I am talking about

http://prntscr.com/e9o00u

It certainly makes sense to insulate your stud wall! That's a good place for Roxul batts. And if you want to improve your house, have the concrete wall covered in closed cell spray foam (2-3") so the whole wall is insulated. As the basement warms up after you insulate, any improvement you make on those walls, you'll notice upstairs quickly. Those walls are "thermal bridges" to the colder temperatures outside and they are carrying away the heat you paid for.

Im sorry, I think i confused when I asked the 2nd question. The primary question is, do i need to place rigid foam in the rim/band joist before i place fiberglass batts in the joice? (Since the joist are so high above the foundation) See picture for more details. Thanks for answering the 2nd part about the studs. Is it common to cover the foundation with spray foam?

It's fairly new, but it is becoming common among people wanting to improve comfort in their home. I had the 1700's portion of the basement does a few years ago - a huge difference in the basement comfort and a major improvement in the room above Looks like your wall has been stucco'd? (the link isn't working well) if so, it will need to be brushed to get off the loose stuff. Spray foam will insulate as well as stop moisture vapor penetration, so you may have a drier basement after (although a lot depends on your floor) Water leaks, if any will run down behind it; doesn't stop those. You'll need to apply a fire retardant paint over the spray foam, or the foam co will do it.

So for the primary question, Rim joist: Do the need spray foam or rigid foam in them before you have fiberglass bats in the rest of the joist bays when the rim joist are so far up and away from the foundation?