Unvented Attic Section

The unvented attic space is completely within the building thermal envelope.

Unvented attic section.

Section 1203 3 says unvented attics where ceilings are applied directly to the underside of the roof framing members are permitted when all of the following conditions are met. 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. The unvented attic space is completely within the building thermal envelope. The unvented attic space is completely within the building thermal envelope.

When designing and building an unvented attic using spray foam insulation you need to take into account code related to. The unvented attic space is completely contained within the building thermal envelope 2. 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. This section outlines the conditions for unvented attic roof assemblies.

The energy savings touted by unvented attics can be as high as 20. Section r806 5 unvented attic assemblies. Where wood shingles or shakes are used a minimum 1 4 inch 6 4 mm vented airspace separates the. Unvented conditioned attics the preference for a large segment of the u s.

No interior vapor retarders are installed on the ceiling side attic floor of the unvented attic. Housing industry has been to locate hvac systems in unconditioned attics but this is highly inefficient. Unvented attic code local codes based on irc 2009. No interior class i vapor retarders are installed on the ceiling side attic floor of the unvented attic assembly or.

Section r316 building thermal envelope code local codes. 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. Section r806 5 spray foam code local codes based on irc 2009. Section r806 4 installation and weather protection.

Unventilated attics can help to mitigate energy loss through leaky ducts or ceiling fittings. Section r316 local codes based on irc 2012. This section indicates that ventilators for roofs are to be installed in accordance with manufacturer s installation instructions and the requirements of section r903. 2009 irc section r806 4.