Vented Attic Fine Home Building

Traditionally building codes have required attic ventilation.

Vented attic fine home building. The recommended ventilation ratio to provide for vented attic assemblies when an air barrier is present is the 1 300 ratio as specified by most building codes. It is my opinion that a vented attic is just never going to be as good as an unvented attic when you move the thermal envelope to the underside of the roof. 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. An improved two zone attic model parker et al 1991 used in the fsec 3 0 program accounts for detailed radiation buoyancy and wind driven airflows and.

Building america research has demonstrated unvented conditioned attics can substantially improve energy performance while allowing home builders to continue locating hvac systems in the attic space. Project house video series. Built in bookcases in an antique home. Mike is building all.

An early attic model fairey and swami 1992 used primarily for modeling the performance of attic radiant barrier systems treated the attic as two zones an upper zone and a lower zone. In order to facilitate this exchange of warm and cool air the general rule of thumb suggests installing at least 1 sq. Of vent for every 300 sq. Building codes vary.

We met up with mike maines at his 1830s greek revival home just in time for him to show us how to install a new fireplace surround. It s one of the more confusing aspects of home building and. The intended purpose was to allow warm air and moisture to escape. With all of the existing home inspections that i did on buildings anywhere from relatively new to over 100 years old a high percentage of the time there were problems.

This is based principally on good historical experience and simple psychrometric analysis handegord giroux 1984. For example this author s home has attic space accessible with a standard door on the second floor and an upper section that can be reached only via a ceiling hatch.