Cold Flat Roof Construction Detail

In case of warm roofs they have an insulation above the roof deck in this way it keeps the deck warm.

Cold flat roof construction detail.

There are several methods and materials for the design of the exterior surface of a warm or cold flat roof. The membrane is then attached to the insulation. 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. 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.

There are three recognised designs of flat roof construction. It must provide adequate protection against the elements keeping the buildings structure and interior dry. No ventilation is required for these types of roofs. A warm deck roof is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation.

Cold deck roof a cold deck roof is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof. Warm roof build ups can be installed on most modern construction material types such as concrete timber and timber based sheets. Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. Warm cold and inverted.

Cold bridging through the system is easier to eliminate or control as ordinarily there are no breaches from the structural supports as there is in a cold roof construction. In a cold roof construction the sarnafil membrane is installed directly to the structural decking usually timber with firrings to fall. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less. Flat roof design guide.

The construction of the flat roof is similar to that of the timber upper floor. Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading. The 3 most common materials used for flat roof construction. Hot tar and gravel.

A flat roof must be strong durable and stable throughout its lifetime. For that reason cold flat roof construction needs to keep in mind the need for unblocked airflow.