about insulating attic

[radstorm]

Not sure if I am in the right area or not..but here goes.

I am needing to put new insulation in my attic. I want to use the roll type and not that blown in stuff. However most rolls I see are of the 16" wide variety, but my attic is 24' off center. How would I fill the gaps?

[HayZee518]

just blanket it across the joists

[radstorm]

Thanks for the feedback hayzee..yes i was thinking of the approach. But what about the air gap it will leave i/e between top of the the joists and the ceiling itself? Will that effect the insulating value? Aslo..would I put a vapor barrier (sheet plastic) across the joists first as well? Right now the ceilings are gone as I will be replacing them with new drywall..so the attic is pretty much easy to access now.

[radstorm]

Thanks for the feedback hayzee..yes i was thinking of the approach. But what about the air gap it will leave i/e between top of the the joists and the ceiling itself? Will that effect the insulating value? Also..would I put a vapor barrier (sheet plastic) across the joists first as well? Right now the ceilings are gone as I will be replacing them with new drywall..so the attic is pretty much easy to access now.

[HayZee518]

you can buy kraft faced fiberglass for 24 on center joist spaces. just staple to the ceiling joist faces. later lay unfaced batts cross ways on top of what will be there. attic insulation should be R-19 or greater.