Flat Warm Roof Build Up

There are two types of flat roof.

Flat warm roof build up.

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. Inverted warm deck roof. There are three recognised designs of flat roof construction. The sandwich warm deck roof is the most common type of flat roof.

The insulation is immediately below the waterproofing layer. The insulation is placed below the waterproof covering and is either mechanically fixed or bitumen bonded on to the top of the deck. In the warm flat roof construction there is insulation packed into every possible space where air can flow. 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.

Pitched or sloping roof a pitched or slanted roof has a terrain of at least 15 but it is often much more. The vapour control layer is above the decking but below the insulation. In creating the cold flat roof air is allowed to circulate freely between the joists and there is no insulation. As opposed to old built up felt roofing with joins new single ply waterproof membranes are now most commonly used.

Cold roofs and warm roofs. The insulation can be adhered mechanically fixed or loose laid. The insulation boards in an inverted warm deck are laid over the structural deck and the waterproof covering. In terms of the thermal design of a flat roof what are the options and the best practices of flat roof build ups.

Warm deck flat roofs can be constructed on most modern construction material types such as concrete timber and timber based sheets. Warm cold and inverted. 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. 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.

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.