Flat Roof Warm Roof Construction Detail

The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure.

Flat roof warm roof construction detail. The vapour control layer is above the decking but below the insulation. Waterproof membrane to prevent water penetrating the structure and interior of the building. Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board. 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.

On a basic level flat roof construction comes in the form of roofing timbers or joists as they are more commonly known or steels that are laid across two uprights walls in most cases. Although flat roofs are cheaper to build than pitched roofs they have a shorter life span. Steve from london flat roofing explains how warm flat roof construction works in this excellent short video. So what is warm flat roof construction.

The insulation can be adhered mechanically fixed or loose laid. A roof is considered to be flat when it is of a slope of 1 5 o to the horizontal. Also known as the built up roof bur this type of flat roof features three or more layers of waterproof material mixed in an alternating fashion with hot tar and a layer of smooth stone like gravel. The membrane is then attached to the insulation.

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. Hot tar and gravel. From there the flat roof system you choose will determine the materials you apply. A warm flat roof is formed by placing a layer of insulation over the top of the roof structure.

Due to the insulation being over the top of the roof the timber structure beneath is warm which is why the term warm roof is formed. It is usually the most acceptable type of construction for domestic possessions and belongings as it avoids the need for aeration of the roof construction. A flat roof usually consists of the following. Warm roofs in case of warm roofs they have an insulation above the roof deck in this way it keeps the deck warm.

The insulation is immediately below the waterproofing layer.