Flat Warm Roof Build Up

In creating the cold flat roof air is allowed to circulate freely between the joists and there is no insulation.

Flat warm roof build up.

Warm cold and inverted. There are three recognised designs of flat roof construction. Pitched or sloping roof a pitched or slanted roof has a terrain of at least 15 but it is often much more. Flat roofs are usually made of variations of bitumen felt and function as durable long lasting roofs that are perfect for water run off in wet weather and protect wood and cement from potential build ups of damp and dry rot.

The insulation boards in an inverted warm deck are laid over the structural deck and the waterproof covering. Warm deck flat roofs can be constructed on most modern construction material types such as concrete timber and timber based sheets. Inverted warm deck roof. The insulation is immediately below the waterproofing layer.

As the single ply roofing association spra points out this type of flat roofing is strong durable completely sealed and usually lasts at least 25 30 years. In the case of a flat roof insulation is usually either a rigid board above the deck or a mineral glass wool quilt immediately above the underdrawn ceiling depending on the type of roof design and construction. In the warm flat roof construction there is insulation packed into every possible space where air can flow. To use epdm for a warm deck flat roof construction solid closed cell roof insulation such as kingspan or celotex should be placed on top of the roof deck rather than in between the rafters.

The vapour control layer is above the decking but below the insulation. The recognised flat roof build ups for best design practices are. In the case of a flat roof insulation is usually in the form of either a rigid board above the deck or a fibrous quilt immediately above the ceiling depending on the type of roof construction. The insulation is placed below the waterproof covering and is either mechanically fixed or bitumen bonded on to the top of the deck.

As opposed to old built up felt roofing with joins new single ply waterproof membranes are now most commonly used. There are two types of flat roof. In terms of the thermal design of a flat roof what are the options and the best practices of flat roof build ups. The insulation can be adhered mechanically fixed or loose laid.

A warm flat roof or a built up roof bur is one where all the insulation is above the joists deck making them part of the warm fabric of the building.