How to insulate old part of house after addition
Hi hope everyone is doing well. I’m adding a side addition to my home. I’m adding a garage that is level with first floor but above basement level. I will also add on a second floor bed and bath above garage. Right now my basement is uninsulated and unfinished. One outer wall of basement will be pretty much buried and next to new foundation. So does that mean that my old basement wall will no longer need insulation? If so do I just build a 2×4 wall with an air gap between concrete and wood to put in wires and plumbing? Or for some moisture reason I need a foam board barrier on wall between wood and concrete. The opposite side of this wall is exterior so I will be insulating that side. Thanks for input, Joe
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Joe,
Your climate zone matters - whether or not to insulate, where and how much depends on it. IECC can give you baseline minimum R values for assemblies.
Whether or not your garage is heated matters. Define your thermal boundary and strive for continuity.
You said you're insulating the exterior of the foundation wall. If you have sufficient R value on the outside, you wouldn't need to insulate the interior. An air gap between your furred wall and concrete is a good idea and is code required for non-pressure-treated lumber.
Best,