Attaching Insulweb to wall penetrations and preventing cellulose blow-out
(1) My ceiling: 24″ o.c.12″ deep rafters/cathedral; I have already installed 1/2″ low-sag Sheetrock glued and screwed horizontally.
(2) My walls: 24″ o.c. Larsen trusses.
(3) No top plates; Larsen truss wall bays pass directly up into the rafter bays. It’s a cantilevered pole construction; building load hangs on 3/4″ rod attached to poles (i.e. 6 X 6 square timbers)
(4) No basement: plumbing and heating PEX, wiring, etc. are in the walls; Stelrad radiators used for heating.
Insulation to be Dense-packed cellulose blown behind ceiling drywall; while on walls, we will blow through Insulweb.
We have generic plastic and metal electrical along with some gasketed electrical boxes in ceilings and walls. The wire penetrations in the boxes are sealed by spot spray foam applied on outside of boxes. When blown, the the dense-packed cellulose will pack up tight to and around the boxes; as well as around the supply and return copper nipples feeding the radiators
1. How should the Insulweb be attached to/sealed to the electrical and pipe nipple penetrations where there are no surrounding framing members? (Otherwise it will be glued and stapled on stud faces.)
2. How do I prep and seal the drywall gaps and spaces so my dense-packed cellulose will not blow out during installation and so it will not leak out later?
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