Insulation R-Values and Kneewalls
As part of my sealing and insulation project for my attic, I’ve been trying to determine what would be considered the proper r-value for insulating the knee walls. I’m assuming it’s somewhere between what would normally be recommended for an area’s walls and for an area’s attic, but that’s a lot of territory. This would be for a vented roof, and for my area of the country summer attic heat is as much a concern, if not more, as winter cold, at least for comfort’s purposes. Insulating the roof, rather than knee walls and attic’s floor, while usually preferable, is not a great option for this house for a number of reasons specific to this house.
So, for instance, I believe in my area, Zone 4, code would state you should R20 for walls and R49 for ceilings, what would you believe the R value should be for knee walls using an insulation goal comparable to the goal the code sought?
Of course, we can always go higher, but I’m just trying for purposes of comparison to get what people would consider comparable to that level of insulation. For others out there in warmer or colder climates that may have similar questions, would your advice vary? I ask because, I’m assuming normal insulation levels for walls would be sufficient in colder climates, but it’s really the extra heat in attics that differentiate knee walls from a normal exterior wall.
Thanks for your help!
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