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Batt Insulation for Existing Vented Attics

Guide describing how to increase insulation in existing homes by installing batt insulation on the ceiling plane of a vented attic.

Right - Raised-heel roof trusses allow more room at the eaves for attic insulation.

Insulating sheathing is extended up to the roof rafters and sealed around the framing with spray foam as part of this exterior wall retrofit

The attic is sealed and insulated along the underside of the roof deck with 5.5 inches of polyurethane spray foam, providing conditioned space for the HVAC system.

On top of the ice-and-water shield, the builder installed horizontal beams that were raised 6 inches off the deck to allow room for spray foam insulation.

Right – This hot-humid climate home is constructed with concrete block that is insulated on the inside with rigid foam; the framing is borate-treated lumber; the roof design is a high-wind-resistant hip roof with only one small gable over the entry.

Publication Date

Thu, 09/30/2021 - 12:00

The OSB roof decking product comes with an adhered radiant foil barrier which helps to prevent heat transfer in or out of the vented attic, while R-13 unfaced fiberglass fills the advanced-framed 2x6 walls.

Cold Climate Building Techniques and Concepts: Cathedral Roofs

Publication Date

January, 2014

Author(s)

Cold Climate Housing Research Center

Organization(s)

CCHRC

Video describing roof and attic construction for cold climates, including cathedral roof design and insulation strategies, from Cold Climate Housing Research Center.

Roof Deck Sheathing and Sealing for Sloped Roofs

Guide describing requirements for sheathing and sealing the roof decking in accordance with the requirements of the IBHS Fortified Home Program's Hurricane and High Wind Standards, and other roofing considerations to increase the roof's disaster resistance.