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grogapuppy
Knee Wall / Adding Insulation

I was up in my attic the other day adding a CAT5 line to an upstairs bedroom and noticed the insulation is curling or bulging past the 2x6 in spots. Insulation is faced fiberglass; but if done like in the kitchen, it was not stapled.

I thinking of placing rigid insulation and some leftover Tyvek on top. Thoughts?

Also one opening was 36" with no insulation or 2x6 in the middle. I think they must have thought of adding a door there. Can I just add a 2x6 and place insulation in with the facing against the drywall?

MLB Construction
Re: Knee Wall / Adding Insulation

everything you said sounds like a good plan to me

Mastercarpentry
Re: Knee Wall / Adding Insulation
grogapuppy wrote:

I thinking of placing rigid insulation and some leftover Tyvek on top. Thoughts?

No to the Tyvek- any vapor barrier belongs against the back face of the drywall between it and the framing. While Tyvek does allow airflow it is not enough in this case and you're better off with nothing. Also you should be seeing the fiberglass, not the paper backing, from the attic side for the same reason. If it's backwards flip it all over.

Quote:

Also one opening was 36" with no insulation or 2x6 in the middle. I think they must have thought of adding a door there. Can I just add a 2x6 and place insulation in with the facing against the drywall?

Sure, and if you don't want to add the 2X6 you can just insulate and leave it as-is. Just remember to never step there when you're in the attic!

It sounds to me like you'd be better off adding blown insulation on top of what you've got to get it up to today's standards (or at least close to that). If you DIY that be sure to use the cardboard stops at the eaves so that you don't block off the soffit ventilation. Insulation can usually be hired out cheaply enough to make it not worth your time to DIY- I haven't installed more than a few pieces in years where we moved or closed in a window or door. More than that I call my insulation guy, then go do something more profitable while he takes care of everything!

Phil

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