Unvented Hot Roof Design

An unvented roof assembly is constructed without any ventilation and is fully sealed on all sides and filled with insulation.

Unvented hot roof design.

Potential pitfalls to avoid include. As a result unvented roofs have become popular in homes with feature dense roofs think multiple skylights dormers and other aesthetic flourishes. We provide data design suggestions for hot roof designs or for providing roof and ceiling ventilation and we describe roof roof insulation or venting system inspection methods and clues to detect roof venting deficiencies insulation defects and attic condensation mold or structural damage problems in buildings covered by an un vented or hot roof or hard to vent roof design. Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction.

These roofs have some pros and cons as explained in the article. Unvented roofs unvented roofs are increasingly common due to design priorities. A powerful argument can be made for unvented roof construction in hot humid climates in order to control interior moisture. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.

Hot roof designs aka dense packed insulated sloped roofs. Sc historically typical construction of homes in canada and the us have vented attics between the ceiling of the interior space and the roof. The disadvantagesof unvented roofs have to a certain degree been overstated in hot climates the extra heat gain from unvented roofs rarely exceeds a couple of degrees celsius. This article describes various cold climate building solutions for un vented cathedral ceilings and similar under roof spaces offering advice on how to avoid condensation leaks attic mold structural damage when roof venting is not possible.

Unvented roof assemblies are becoming an increasingly common construction alternative to traditional vented roofs. An understanding of heat air and moisture as well as the causes of condensation is critical in detailing unvented roof assemblies. Four options for building an unvented roof assembly. Unvented roofs operate by the principle that venting is not necessary to control moisture accumulation.

When properly installed unvented roofs perform well and cause no excess moisture accumulation. Practicality is also enhanced. This definition allows simple unvented roof design just don t install vents in a previously recognizable climate zone ashrae s hot humid zone. They are designed without ventilation openings and the attic is conditioned like the rest of the living space.