EPDM Roofs explained


All the things you need to know about EPDM .

Epdm Explained

EPDM stands for Ethylene Propylene Diene Monomer, a synthetic rubber used in a range of applications.

it is used in a number of applications not just as a roof waterproofing membrane

Its used for tanking ponds, motorway bridges enveloping basements alongside other uses.

It is highly elastic so can handle movement in a building a lot better than some of there other more rigid products that are on the market for today's flat roofing systems including GRP and High performance flat roofing systems.

Epdm has no toxic vapours so is good for the environment.

These roof systems are cut to size of the roof up to 300 square metres if you used a Prelasti system with joints being vulcanised under factory conditions.

systems over 60 square metres are heavy to carry so its a good idea to factor how you are going to get the sheet to the roof.

The benefits of the system in my opinion is best when you have a roof system with minimal protrusions and under 300 square metres as it is truly seamless. However you need to be careful because there are manufacturers in this market that do not have the facility for sheets being made to such a size and on larger roofs there solution is to join with a joining strip which to be fair is not a seamless roof system is it. So stay away from that type of roof system. These are typically bought from the internet and you have to be aware that any one can buy these without any training to install so be careful when instructing a contractor and check that he is a licensed installer for the product he is going to lay.

Even with a seam, EPDM is waterproof however it undermines the roof systems benefiting from a SEAMLESS APPLICATION and is a weak spot in the system. Like most things that you buy the Manufacturers will always tell you this is greatest thing since bread and jam but in reality that is not always the case, you might end up with a stale moldy bit of bread to use a metaphor. If a leak does develop, it is usually easy to repair, so can be inexpensive. EPDM roofs are fire resistant. ... In fact, even with only minimal attention, an EPDM roof can last 50 years or so but like all roof systems will need to be maintained properly and should be inspected annual.

A typical domestic EPDM installation
A typical domestic EPDM installation

i would not recommend specifying it to a building with lots of detail pipe protrusions bits sticking out etc but has lots of benefits on a roof deck with minimal detailing

To be fair there is no superior roof system from one type of roof system to the next and when specifying a roof system it is usually determined on the individual roofing project.

However EPDM is a extremely good product and I would favour this type of roof system above say a GRP roof system in terms of install practicality and its high elasticity it is a more versatile product.


  • roof system with no joins
  • high elasticity
  • long life span
  • made from recycled materials
  • licensed trained installer roofing system


  • the look of this type of system is not great as it just looks like black rubber
  • there is only one layer
  • cheap versions on the internet of low quality products
  • not so good for high detailed roof

If you would like our free flat roofing guide in conjunction with the flat roofing alliance then please click here