EPDM Rubber Flat Roof Membrane – FAQs

Frequently Asked Questions – Rubber Flat Roof. Do you have any other questions for us? Send us an email at: sales@rubberflatroof.co.uk or call us on: 01392 927729.

I’m not sure what I need to build my flat roof, what’s the best way to know?

We have the perfect way to rectify this issue, all you need to know is the measurements of your roof and we can do the rest! Check out our Roof Quote Tool by clicking here, input the information which you have about your roof and we will put all the materials which you will need into your basket for you. If you aren’t sure what they are useful for, either check out our step by step videos which can be found here, read the product descriptions, or get in touch.


How long will RubberCover EPDM membrane last?

At Rubber Flat Roof, our high-quality RubberCover EPDM - Flat Roofing Membrane in 1.14 & 1.52mm thicknesses, both carry a FREE 20 year warranty. However, EPDM membranes have been proven to have a life expectancy of more than 50 years, even when exposed to sunlight. Read more here.  

  • The saturated polymer backbone allows for strong resistance to weathering, high heats, and temperature. 
  • The chemical properties of EPDM result in a very low risk of oxidation and any related damage.
  • There is high resistance to water, acid and alkali erosion. 
  • The EPDM membrane is a non-polar elastomer, which affords it a high electrical resistivity.
  • It has flame retardant properties and a highly flexible membrane – capable of up to 300% movement.


Is maintenance required?

No specific maintenance is required for a RubberCover EPDM roofing system. However, we recommend an inspection of the roof twice a year, or after particularly bad weather. Read more here


Can certain materials damage RubberCover EPDM?

RubberCover EPDM is less resistant to oil products. Contact with mineral and vegetable oils, petroleum-based products, fresh bitumen and grease must be avoided. 


How can my EPDM roof be repaired in case of damage?

The membrane can be easily repaired using a seam tape primer and a piece of self-adhesive Flashing Tape. Read more here


Must the roof surface be cleaned before adhesion of EPDM Rubber?

The surface must be clean, smooth and dry. The surface must be free of sharp and/or loose objects and/or foreign materials such as oil, grease, and/or other contaminants. Therefore, it is recommended to sweep the substrate with a brush prior to the installation of the membrane or use a leaf blower to blow away any debris.


Are specific tools required for installation?

Besides the  ScrubPad tool and hand roller, the following tools are needed: scissors, tape measure, solvent resistant roller, chalk line, bucket, mixer (for Bonding Adhesive), clean rags, broom and a hammer to install the Quicktrim system. 


Can I walk on a RubberCover EPDM roof?

The roof can be accessed for periodic maintenance. In case of regular roof traffic, the membrane must be protected with pavers or protective matting.


Can RubberCover EPDM be combined with a Green Roof System?

A sedum green roof can be placed over the RubberCover EPDM membrane, provided that a root resistant geotextile is used between the vegetation and the membrane. A distance of 30cm must be taken into account between the vegetation and every roof installation detail.


Is there a warranty for RubberCover EPDM membrane?

Yes, RubberCover provides a 20 year material warranty.


Can RubberCover EPDM sheets be joined?

Yes, RubberCover EPDM Membranes can be easily joined using either the 3″ seam /splice tape or some 6″ Cover Tape. Primer must be used when joining two sheets as the self-adhesive tapes will only adhere to a primed surface.


Why do bubbles or wrinkles form after the membrane is fastened?

Solvents in the adhesives, which are not allowed to “flash off” or evaporate, cause distortions or bubbles. The wet adhesive distresses the membrane causing wrinkles. Depending on the substrate and the amount of wet adhesive, bubbles or distortions in the membrane will eventually be absorbed by the membrane and disappear.


Can the adhesive dry too long?

Yes. After the adhesive is applied and has flashed off, the surfaces should be mated together. Allowing the prepared surfaces to remain open longer than necessary risks contamination from dust and debris. High temperatures, as well as falling cool temperatures and moisture, can affect the performance of the adhesives if the prepared surfaces are left open too long.


Can I install outdoor carpet over an EPDM roof?

Yes. The best method is to fully attach the carpet using an exterior grade carpet adhesive.


Can I fasten EPDM to concrete or wood?

Yes. Both substrates should be free of splinters, burrs, loose fasteners, sharp edges, dust and debris.


What temperature is too cold for a successful installation?

Adhesives perform best at temperatures over 10°C. Below 10°C, it is best to install only on full sun days with low air moisture content. Application may only be possible during the middle part of the day when the temperature is stable and humidity is lowest. Rule of thumb: if it is comfortable to work in, you can install EPDM. It just takes longer for the adhesive to flash off.


Can I use Rubber Flat Roof EPDM below grade?

Yes. Rubber Flat Roof EPDM can be used below grade as a waterproofing membrane on basement walls, water retention ponds and earth homes. It is important that the substrate be free of burrs and sharp edges that could puncture the membrane. Earth homes and sidewalls should have a barrier board between the membrane and the backfill.


Is Rubber Flat Roof EPDM Membrane safe to use in ponds with aquatic life?

No, most flat roofing membranes have been modified with chemicals to improve fire performance. For ponds a pond-lining EPDM should be chosen instead such as our QuickLiner membrane


Can I install EPDM over smooth surface asphalt or shingle roofs?

Installing EPDM over old smooth surface asphalt or shingles is not recommended. The adhesives used to bond the membrane will activate “dead” asphalt and not bond properly. A retrofit or insulation board should be installed over the old substrate.


When I adhered the membrane, several wrinkles occurred. Will the wrinkles affect the roof?

Although wrinkles are unsightly, unless they traverse a seam, they will not leak. Large wrinkles can be cut out and patched. Small wrinkles might be absorbed into the membrane as it goes through several expansion/contraction cycles. Any wrinkles that migrate through a seam must be removed and repaired.


When should I use 1.14mm and when should I use 1.52mm EPDM membrane?

1.52mm membrane is recommended for roofing applications such as Green Roofs, Solar PV insstallations or Accessible roofs (with a protective cover). 1.14mm membrane as a roofing membrane can be used for most other roofing applications such as extensions, dormers, porches, garages, carports, sheds and garden rooms. You can also check out our EPDM Rubber Shed Kit here.