Blog

Bitumen VS EPDM

May 14, 2021 | General

For years and years, Bitumen (felt) was known to be the leading flat roofing product that everyone turned to. However, since being used to install roofing on houses and garages, in the 1960’s, complaints began to filter through about how unreliable and ineffective this roof covering was. Although Bitumen roofing today comes with its own benefits and disadvantages, EPDM has since been introduced as a strong competitor.

What is Bitumen Felt?

Modified Bitumen is a common flat roofing material that consists of a tar like substance derived during distillation of crude oil mixed with sand or crushed limestone, that has been mixed with modifiers to give it that rubbery effect. Made out of three layers of boards, tar and mineral, Bitumen felt roofing is laid with a naked flame.

What are the disadvantages to Bitumen?

Since Bitumen is laid with an open flame, this can increase the risks of leaking when the proper roofing barrier is not installed with water-tight qualities. Other problems that can occur with Bitumen roofing are inadequate head water and backwater laps which allow for any moisture infiltration. These can all lead to roof failure, causing a shorter life span of around 5-10 years only.

What are the benefits of EPDM?

For ease, EPDM can be installed in a single piece, limiting the amount of join issues that could occur such as leakage through a join so has an easier installation process.

Life expectancy of EPDM is far greater than the lifespan of Bitumen. Here at RubberRoofs our EPDM comes with a 20 year warranty.

Although EPDM can be that much more pricey, you certainly get what you pay for. Quality. Although nearly double the price of felt, the life expectancy of EPDM is three times more than felt.

Unlike felt where the main concern is the use of a naked flame, EPDM is safer with the flame-free and heat-free installation process. It will not only be a faster and smoother process, but will minimise the risk of any damage caused to both the roof's surface.

Lastly but not least, the aesthetic of Bitumen felt can come across as slightly old fashioned and dull. Although it can be installed in many colours to suit the building, grey is the standard colour that bitumen roofing is fitted in. In comparison to EPDM, which has a far more modern aesthetic to it, with its much smoother finish with hidden seams and joints that are visible on felt roofing.

For more information on why EPDM should be a top choice for your DIY project, head over to our website or check out our most recent blog section.