Cellulose Install for a Staggered Stud Wall
We’re designing a series of 24-unit Net Zero apartments in Albany, NY and planning for a 2×8 staggered stud wall. We’re getting concerned about the feasibility of insulating with dense pack cellulose since it’s not easy to create closed cavities. The wall has bearing 2×6 studs @ 24″ o.c and staggered non-bearing 2×4 on the other side of the 2×8 plate.
I’ve thought about netting stapled diagonally from 2×6 to 2×4 to create side dams (a lot of labor), or perhaps strips of fiberboard tacked to studs and extending back to the wall sheathing. I see from prior article “Details for Insulating a Double Stud Wall with Cellulose” a comment from Jonathan Tauer mentioning installing the insulation in multiple passes so that it starts to dam itself into cavities. This seems tricky to ensure uniform consistency though.
If anyone has experience in this domain we’d appreciate your thoughts.
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On a 2x6 top & bottom plate with staggered 2x4's at 12" oc (24" oc at outside wall/ staggered 12" over and 24" oc at inside wall) I have a damp applied cellulose install. It worked well.
They also did a dense pack on one interior wall using netting, because the gyp had not yet been installed. The dense pack settled and I could see light through the top within a day. Then they refilled it, it settled again and now that wall bulges. I think it is much less likely you get a crew that has the skills to do dense pack correctly. Far more likely to get a crew that has skills to do damp applied correctly.