Unvented Sip Roof

The roof is currently built as follows.

Unvented sip roof. This document provides a brief description of different types of unvented roof assemblies and the benefits of unvented roof construction. Create a cold roof by applying a layer of sheathing over 1 3 furring 16 in. This receptor is an air space that can be accomplished in a variety of ways. If you would like to receive a price quote on a sip project please request a sip quote.

Next i ll be screwing down 5 1 2 raycore sips panels over heated space and framing boxes over the eaves covering everything with 5 8 cdx. When constructing unvented roofs with asphalt shingles in hot humid climates a vapor barrier must be installed between the asphalt shingles and the roof deck. This style of roof helps to prevent moisture buildup. According to the builder s guide to structural insulated panels sips published by building science corporation the typical reduction of shingle life over an unvented sip roof assembly is between one and two years.

Venting at the ridge and eave allows air to move freely between the two layers of sheathing. 3 8 plywood diaphragm seams taped. Integrated sheathing and roof deck for a one stop roof framing product. Therefore an unvented sip roof is permitted under irc r806 5 unvented attic and unvented enclosed rafter assemblies.

The 2012 irc permits unvented roof assemblies including unvented sips. Un vented roofs operate on the principle that moisture entering the roof assembly can be controlled and that there is no need for venting to control moisture accumulation. With tribuilt granulated self adhering underlayment on top of the plywood. Four options for building an unvented roof assembly.

Need to make a final decision on which underlayment to use under a metal roof on an unvented roof system. Unvented roof assemblies should be insulated either with air impermeable insulation rigid foam or spray polyurethane foam or with a combination of foam and air permeable insulation. 1 1 2 t g decking. In order for an un vented roof assembly to function properly the following conditions must be in place.

Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. Beams on 5 centers. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck. With an unvented sip roof the argument would be that the exterior osb facing constitutes the structural sheathing referred to in the code.

Asphalt shingles store water from dew condensation due to night sky cooling and rain. Factory engineered and precut per floor plans all but eliminating measuring or cutting material for roof structures.