Unvented Attic Section

Unvented attic code local codes based on irc 2009.

Unvented attic section.

Section r806 5 spray foam code local codes based on irc 2009. Unventilated attics can help to mitigate energy loss through leaky ducts or ceiling fittings. 2012 irc section r806 5 unvented attic assemblies unvented attic assemblies spaces between the ceiling joists of the top story of the roof rafters shall be permitted if all of the following conditions are met. Section r806 5 unvented attic assemblies.

Housing industry has been to locate hvac systems in unconditioned attics but this is highly inefficient. 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. To provide an unvented conditioned space for locating hvac equipment in the attic and or to provide a continuous thermal barrier for designs that have complex coffered ceiling planes and or numerous penetrations for lights speakers vents soffits etc which make it difficult to achieve an airtight ceiling plane. No interior class i vapor retarders are installed on the ceiling side attic floor of the unvented attic assembly or on the ceiling side of the unvented enclosed roof framing assembly.

2009 irc section r806 4. However if moisture is able to enter the unvented attic space it may lead to roofing panel issues. This section indicates that ventilators for roofs are to be installed in accordance with manufacturer s installation instructions and the requirements of section r903. No interior vapor retarders are installed on the ceiling side attic floor of the unvented attic.

Unvented conditioned attics the preference for a large segment of the u s. When designing and building an unvented attic using spray foam insulation you need to take into account code related to. Where wood shingles or shakes are used a minimum 1 4 inch 6 4 mm vented airspace separates the. No interior class i vapor retarders are installed on the ceiling side attic floor of the unvented attic assembly or.

Section r806 4 local codes based on irc 2012. Section r806 4 installation and weather protection. The unvented attic space is completely within the building thermal envelope. The unvented attic space is completely contained within the building thermal envelope 2.

Section r316 building thermal envelope code local codes. Section r316 local codes based on irc 2012. This section outlines the conditions for unvented attic roof assemblies. The energy savings touted by unvented attics can be as high as 20.