EPDM roofing (Ethylene Propylene Diene Monomer) systems are an excellent choice for flat commercial roofs.

The best quality of EPDM commercial roofing is the excellent 300 percent elongation factor. The reason this is so important is because expansion and contraction is a huge problem on large commercial roofs due to temperature/climate changes.

The EPDM membrane easily expands and contracts with the roof structure without damaging the roof membrane.

Clues and caulks are rarely used for EPDM seams. Often, these dry out and pull apart. Most EPDM seams have three-inch or six-inch wide, factory-made seam tape. Seam tapes provide a much better, higher quality EPDM roof field seam.

EPDM systems have three different application types.


In a ballast weight-down system, a #5 washed river rock is used to weigh down the loose laid insulation and EPDM membrane.

This requires 1,000 pounds (half ton) of rock per 100 square feet. We do not highly recommend this ballast system, because of the stress/weight-load factor on the roof structure; weight often pulls the EPDM membrane away from the parapet walls.

It can become very hard to make any necessary repairs, because of the rock that must be removed from the area where leaks occur.

Also rock dust and dirt that adheres to the roof membrane surface make it extremely difficult to make any repairs.


This mechanicallyattached commercial roofing system has insides of seams mechanically attached with two-inch seam plates and #12-14 roof deck screws.

This mechanicallyattached system is also installed easily and quickly. The center of the EPDM membrane floats, as it is only attached in the roof field seams.

Some EPDM membrane sheets are five feet wide, and some are 10 feet wide, with rows of fasteners attached the same width.


In this fullyadhered (glue down) system, the entire EPDM membrane and the face of the roof insulation is 100 percent fully adhered with bonding adhesive.

This is the best application for EPDM roofing, since the entire roof is tightly and firmly secured with the adhesive. This is also the most costly, taking more time and materials for application, however, you will save money in the long run with less need for repairs in future.

EPDM Roof Repair

EPDM rubber roofs are fairly easy to repair. The most important part of any roof repair is to find out where water is leaking through, so a thorough inspection of the leaking roof areas is the first and most crucial step for any roofing company to take.

Note: Oftentimes, where the leak is coming through the ceiling may not be where the leak is actually found. This is because the water is following the corrugated roof deck, or the bottom of the existing roof. Water can flow a long way sometimes, and it may be a bit tricky finding the problems.

Sometimes we can fix a leak with just a small EPDM patch at the leaking area. Other times, there are several areas that need repairs. Depending on the overall condition of the roof, it may be necessary to repair larger sections of roof.

Ballast weight-down roof with rock covering the entire EPDM membrane can make it very difficult to find the leak and make necessary repairs. All of the rocks must be removed from the leaking areas, and then a vigorous cleaning process is undertaken, to remove all rock dust and dirt that adheres to the surface of the roof membrane.

Q. Do you guarantee roof repairs?

A. We do not guarantee small spot repairs. If we perform overall roof repairs and maintenance on the entire commercial roof system, we may guarantee our work for one to five years, depending on the condition of the roof and what is involved in the repair or maintenance process.

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