Warm Pitched Roof Build Up

In this blog post we explore some of the options available.

Warm pitched roof build up.

There are a couple of different methods for constructing pitched style roofs. When insulating a pitched roof at rafter level there are a number of key design considerations which will affect the build up of the roof and the choice of insulation. There are typically two different ways to insulate a roof a warm roof and a cold roof. Warm pitched roof ventilated and sealed.

Pitched or sloping roof. In building construction roof pitch is a numerical measure of the steepness of a roof. The enclosed void of a warm pitched roof does not require to be ventilated. Rather than actively ventilating to the outside entrapped water vapour diffuses.

Warm roof build ups can be installed on most modern construction material types such as concrete timber and timber based sheets. In areas of high snowfall then the roof pitch can be much greater to allow the snow to fall off the roof rather than settle and build up on the roof. Insulating the roof above the rafters is known as warm roof insulation as the rafters are brought into the insulated envelope of the building. A pitched or slanted roof has a terrain of at least 15 but it is often much more.

With the potential of additional living space a cathedral roof design or a conditioned roof void are rapidly becoming the preferred choice of. Insulating a pitched roof above the rafters is the common method chosen for new builds and re roofing existing detached buildings as it provides superior thermal performance for the building. They can be built up from profiled metal decks as the insulation selected would provide enough rigidity to span the open sections of such decks. This is more of a traditional manner in regards to cutting the timber while onsite and building up the roof by the use of rafters ridge boards joists and purlins among others.

Firstly just to make it clear when we are talking about rafter level we mean the timbers that support the pitched roof. Warm roof in a warm roof construction the principal thermal insulation layer is located above the structural decking resulting in the structural deck and support structure being at a temperature close to that of the interior of the building. One pitched roof construction method is a cut roof method. Ventilation and the potential condensation risk associated with large voids of cool air make this the optimum pitched roof solution.

A warm roof building will make the entire structure of the building warm in an attempt to avoid any cold bridging. With the introduction of vapour permeable plastics underlays the need to create ventilated voids above inclined insulation and the requirement to ventilate cold roof lofts may be reduced. Warm cold and inverted.