Green Building How To Build A Conditioned Attic

This has several advantages including less air transfer and what air does transfer is conditioned.

Green building how to build a conditioned attic.

Watch this if you ve not seen it. In an unvented attic assembly air impermeable insulation is applied directly to the underside of the structural roof deck and is tied into the insulation located in the walls so that the roof system becomes part of the insulated building enclosure. The attic space becomes indirectly conditioned as a result of the air leakage heat transfer and. In warmer climates unvented attics can prevent the condensation that occurs on ductwork in some vented attic spaces.

The roof deck in an unvented attic must be exceptionally airtight. Department of energy through the building america program to research conditioned attics in nevada and texas. 5 dumb ways to build in the south. After experimenting with cellulose insulated roof assemblies and fiberglass insulated roof assemblies lstiburek began promoting conditioned attics.

My original plan was to build a conditioned attic and place 1 5 of foam xps board r7 5 installation on top of the roof deck and fill the old true 2x4 rafters and rafter walls with closed cell insulation and if able attach 3 of foam xps board r15 to the rafters in the attic. The irc has permitted unvented conditioned attics since 2006 with certain requirements. You can reduce dust buildup using an unvented attic versus a vented attic. In a roof attic assembly the builder has two choices.

The acceptance of unvented conditioned attics continues to grow among builders and building officials. The loss of energy efficiency means some designers choose to move the ductwork into the conditioned areas of the home and leave the attics unvented. Unvented attics are built with insulation of the attic is placed at the roof level and the area inside the attic is a conditioned space. Install insulation along the underside of the roof deck of an unvented attic rather than on the ceiling deck of a vented attic for either of two reasons.

During the 1990s the building science corporation received funding from the u s.