Non Vented Roof Systems

Unvented roofs which provides a detailed explanation of each.

Non vented roof systems.

Basically the term cold roof refers to a traditional roof or vented roof while hot roof refers to a roof that is not ventilated and which has foam insulation attached directly to the roof sheathing. In this case you can learn a lot from foam tech s article vented vs. I have roof vents so i have roof ventilation. Unvented roof systems can be safely used in many different climates.

In cold climates insulating sheathing must be added exterior to the roof sheathing to prevent condensation on the underside of the roof sheathing. The roof assembly has enough insulation and it is properly installed. Icynene s open cell structure easily allows any moisture or water vapor intrusion to quickly drain and dry out. Take for example ridge vents.

However designers of compact roof assemblies must consider vapor permeance and arrangement of the roofing materials to produce acceptable hygrothermal performance and low. 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 any roof system there should always be a contingency plan to address the possibility of roof leaks especially with wood roof decks. The quest for greater energy efficiency in buildings has led to increasing interest and need for insulation improvements in hvac equipment more airtight construction new materials and assemblies.

The building envelope is tight enough to prevent warm moist air from escaping from the building interior into the roof assembly. Senior engineer manager at icynene john broniek makes the case for the unvented attic assembly and why insulating the underside of the roof makes sense. While hardly anybody agrees on the best roof ventilation system everybody agrees some roof vents do hardly any good at all. The truth about insulation performance in the real world of buildings.

Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. 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. An unvented roof assembly is constructed without any ventilation and is fully sealed on all sides and filled with insulation.