Flat Roof Construction Layers

Since 2005 if you replace 25 or more of your roof covering felt then you need to ensure that the entire flat roof has enough insulation to satisfy current building regulations.

Flat roof construction layers.

Known technically as elastomeric or plastomeric roof membrane depending on the material single ply roofs come in a few different varieties including. For that reason cold flat roof construction needs to keep in mind the need for unblocked airflow. Hot tar and gravel. Four plies denotes a four layer flat roof membrane system.

Flat roofs usually come with a 10 to 20 year warranty but can last 25 years if you build the roofs right and maintain them using commonsense rules. Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs. This could mean flat roofs may not raise the same red flags they used to. Pvc single ply membrane arguably the most popular of all flat roofing materials some contractors even install only pvc membranes for higher end residential installations pvc membranes are a single layer of thermoplastic material.

In short any roof covering that can make a flat roof waterproof in one layer unlike roofing felt with its 3 layer system for instance. But now flat roofs often are constructed with fewer layers because of improved waterproofing technology. Built up roof bur the traditional hot tar and gravel. Steep sloped roof products such as tile slate metal and shakes only allow one layer.

On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing. Flat roofs are hard to replace. There are several methods and materials for the design of the exterior surface of a warm or cold flat roof. The 3 most common materials used for flat roof construction.

The number of plies on a roof implies the number of layers i e. Roof covering typically of flat and rectangular shapes and made of various materials such as slate wood flagstone plastic metal and composite materials. Pvc roofs are especially strong and durable featuring a minimum breaking point of 300 pounds per inch. For many years it was acceptable to put even the third layer.

This only applies to flat roofs over habitable parts of your home so it excludes garages sheds some porches and most door canopies. All three types of flat roofing cost 250 to 350 per square 100 square feet but prices vary according to region and size of the roof. The felts are reinforced with either glass fiber mats or organic mats ply sheets and when joined with the bitumen form a durable roofing membrane. The membrane roof is the latest roofing technology and is also the roof of choice in commercial construction.