Together with not having to provide a ventilation pathway the technique permits insulation to be installed within the full depth of the rafter.
Unventilated roof construction.
Eliminating traditional ventilation and the potential condensation risk associated with large voids of cool air make this the optimum pitched roof solution.
Cold roof decks and external cladding or tiling.
Breather membrane in colours.
For designers the advantage of using unventilated construction comes from removing the necessity to provide a ventilated cavity below the sarking.
This document provides a brief description of different types of unvented roof assemblies and the benefits of unvented roof construction.
Control construction moisture content with tenting or temporary roofing when necessary.
Because the drying capacity of unvented roof assemblies is inherently lower than vented ones it is especially critical to control built in moisture during construction.
Poorly insulated ducting can cause heat loss in colder months and the loss of conditioned air in the summer in vented attics.
Moisture content in roof structure must be less than 18 prior to covering.
Unventilated attics are common where roof assemblies are complex and it s difficult to create a sealed ceiling plane.
The ever increasing levels of thermal insulation required by thermal regulations can result in a higher risk of condensation forming on those elements not enclosed by this insulation e g.