Different Types of Flat Roofing Materials

The quality of bricks and mortar is vital for laying down foundations; similarly the quality of a roof to uphold a structure is just as important. There are a wide variety of flat roofing materials to choose from which are subdivided to suit the type of flat roofing. Flat roofing generally falls under three categories:

Built Up Flat Roofs (BUR)

The roof is built up using several layers of saturated –tar paper, liquid tar or liquid asphalt or modified Bitumen acting as a roof membrane. Layers and layers of the material are laid down in a criss cross pattern until a satisfactory secure numbers of layers have been reached. As an added measure a layer of gravel is placed on top to help further protect it from the suns unrelenting rays.

Single Ply Roofing

This is the most commonly used type of roofing where just a single layer is laid down.  This type of roofing is much thinner and lighter using materials that have both waterproof and weather resilient properties.

Single Ply Roofing comes in different forms where some are made from EPDM Rubber. The Rubber roofs are usually black, unenforced and use adhesives to secure the seams and be watertight.

PVC (Poly vinyl chloride) and TPO (Thermoplastic Polyolefin) are also used as flat roofing materials. They are white and reinforced with hot air welded seals. They require specialist equipment to install and weld the seams. They both work in similar fashions except TPO is relatively newer and a cheaper alternative to PVC.

Liquid applied Roofing

This particular flat roofing system uses two methods of applying a liquefied protective coating on the roof to increase its durability. The two methods employed are Spray foam coating  (SPF)and Roofing coating

Spray foam coating is where primary and secondary insulation is sprayed directly onto the roof and then reinforced with a coating of acrylic or urethane. This coating is then covered by a layer of crushed sand or stone for added protection.

The coating is essential for long term performance and to prevent UV rays from the destroying the insulating foam. Ideally SPF roofs should be recoated every ten years to maintain its performance and leak free reputation. However the leak free notion isn’t entirely free from error as birds have a tendency to eat away at the insulation causing perforation and leaks. These can be easily repaired and the advantage of SPF roofing is the tight seal created and seamless insulation.

Roof coating

This has been primarily designed to coat existing roofs and extend their performance by up to 15 years. They act as an additional waterproof layer although not all tend to.

Roof coatings are most effective when used on smooth surface roofs such as the older EPDM roofs, low sloped metal ones or the modified bitumen roofs. The coating isn’t well suited for tar and gravelly roofs as the debris and dirt that collects makes the surface uneven. It is important to have a smooth surface for full even coverage.

The best roofing material is one that is long lasting, weather durable and minimal maintenance is required. A proven track record is important to consider, and although the material may be more expensive, in the long run the quality will withstand against the elements and prove to be money well spent.