Unvented Roof Systems

As a result unvented roofs have become popular in homes with feature dense roofs think multiple skylights dormers and other aesthetic flourishes.

Unvented roof systems.

Sc historically typical construction of homes in canada and the us have vented attics between the ceiling of the interior space and the roof. These roofs have some pros and cons as explained in the article. An unvented roof assembly is constructed without any ventilation and is fully sealed on all sides and filled with insulation. Many local building codes do not account for non standard construction alternatives such as unvented attic assemblies.

A system most likely to be found in newly built homes. When properly installed unvented roofs perform well and cause no excess. Ventilation becomes more difficult the more complicated a roof s construction is. Controlling ice damming by keeping the roof cold.

While unvented attics are gaining acceptance homeowners must realize their limitations including. Enhancing roofing material life span by reducing sheathing temperature. Unvented roof systems can be safely used in many different climates. An unvented assembly can perform well but it s important to get the details right to avoid sheathing rot.

Unvented roofs vented roof. Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. Removing moisture from roof cavities structural members sheathing and insulation. However designers of compact roof assemblies must consider vapor permeance and arrangement of the roofing materials to produce acceptable hygrothermal performance and low.

Unvented roofs have a number of advantages. There are traditionally four main reasons for venting a roof. Unvented roof systems where the insulation and air barrier are applied directly to the underside of the roof deck are common in applications where designers are seeking cost effective and energy efficient roof assemblies. In cold climates insulating sheathing must be added exterior to the roof sheathing to prevent condensation on the underside of the roof sheathing.

These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.