Attic storage insulation details
DennisDipswitch
| Posted in General Questions on
Attic storage — some people gotta have it. What would be some ideas to insulate this type of area where a plywood walking surface is necessary, and joists are shallow (2x6s)? What about pull-down stairs?
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Replies
Dennis,
If the existing ceiling joists are too shallow for the depth of the required insulation, you need to install more framing to raise the floor. If you need another 5.5 inches, install 2x6s -- either on top of the existing joists (stabilized with blocking if necessary), or perpendicular to the existing joists. If you need more depth than that, choose 2x8s or 2x10s.
Pull-down stairs are notorious air-leakage sites, and are almost always poorly insulated. I think that pull-down attic stairs are a bad idea, but if your house has them, here are some suggestions: "How to Insulate and Air-Seal Pull-Down Attic Stairs."
Martin,if the access,pulldown stairs,are always going to be a weak link,would it be sensible to just move the thermal envelope up to the rafters?Insulate the rafter bays,build and insulate knee walls,and sheetrock,tape,spackle? If this is done,what becomes of the r -19 in the ceiling?