Attic insulation in older home without raised heel trusses
Renovating a home in Zone 4. Rafters are 2×4. Built in 1972. Rafters rest directly on sill plate top of 4″ block wall with brick veneer. Low slope roof, 5/12 (22 degrees). Tallest point is 5′ inside attic. There is no raised heel. Interior gut job. Owner wants to keep existing rafters, replace plywood roof, underlay, shingles. Looking to put insulation at roof line. 5″ nailable polysio insulation on top of 2″ polysio (total of 7″ insulation – R38), then 5/8″ zip systems OSB on rafters; blown-in cellulose (3.5″) interior between rafters with netting. This to achieve R49.
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