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.
Flat roof construction layers.
Roof covering typically of flat and rectangular shapes and made of various materials such as slate wood flagstone plastic metal and composite materials.
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.
It is a waterproofing layer made of regular felt stacked above the solid decking board and then completely covered by the shingles or other roofing materials.
Asphalt shingles typically can have one more layer added over the top two roofs total.
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.
The 3 most common materials used for flat roof construction.
The number of plies on a roof implies the number of layers i e.
Known technically as elastomeric or plastomeric roof membrane depending on the material single ply roofs come in a few different varieties including.
The membrane roof is the latest roofing technology and is also the roof of choice in commercial construction.
This could mean flat roofs may not raise the same red flags they used to.
Flat roofs are hard to replace.
Four plies denotes a four layer flat roof membrane system.
This can include epdm rubber and fibreglass talked about above but commonly especially in the trade and in this article it refers to pvc tpo tpe and pib.
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.
For many years it was acceptable to put even the third layer.
Built up roof bur the traditional hot tar and gravel.
There are several methods and materials for the design of the exterior surface of a warm or cold flat roof.
This only applies to flat roofs over habitable parts of your home so it excludes garages sheds some porches and most door canopies.
Hot tar and gravel.
On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing.
Pvc roofs are especially strong and durable featuring a minimum breaking point of 300 pounds per inch.
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.
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.
But now flat roofs often are constructed with fewer layers because of improved waterproofing technology.
