EPDM Roofing: Installed on Commercial Roofs Despite Defects
Ethylene Propylene Diene Monomer, also known as EPDM, is a synthetic rubber with an elastic nature and is the same type of rubber used to make inner tubes of tires. EPDM rubber has been installed on commercial roofs for decades, despite its poor performance, since the late1970s. The rubber membrane tends to shrink and degrade prematurely from harmful UV rays, and the adhesive fails to maintain a bond at the seams. Since then, it has gone through several generations of “improvements.” Manufacturers claim that UV and ozone protection is inherent in its formulation. Although the defects are in revision at least four times since first being manufactured, each revision has been ineffective to extend the life of the rubber and adhesives adequately.
Its popularity is due to “Smart Marketing” strategies that pertain to cost-effectiveness. The 20 ft wide membrane, its elasticity, the ease of installing with little experience, and very few inexpensive tools needed, are just some claims. None of these strengths, however, address the defects of the still, inferior formulations, to date.
Advocates for EPDM often refer to it as an “Extremely durable synthetic rubber roofing membrane,” but do not mention another system as a comparison. When compared to the Two Ply Modified Bitumen Torch Down Roofing System, EPDM is far from having a standard of durability, without frequent problems with defective formulations.
EPDM Membrane Roof Installed on Commercial Roofs: “Popular on the Surface”
Although the EPDM Membrane Roof is a popular roofing system, it is far from the best roof money can buy.
- EPDM has a smooth finish which looks and feels nice to walk on and to touch.
- The smoothness of the rubber makes sweeping or leaf blowing easier.
- It is manufactured in wide sheets of 8 – 20 feet which reduce the number of seams that need adhesion.
- Installation is relatively inexpensive because it is not labor intensive to install, and few tools are needed.
EPDM: “Under the Surface”
- EPDM rubber membranes come in .45 and .60 Mil., which is only about 1/16″.
- The formulations of both the rubber and the adhesives are in their 5th generation of revisions because of a premature failure to perform; after about ten years of UV exposure, the rubber shrinks and the adhesives fail to maintain a bond.
- It requires constant maintenance throughout the life of the rubber membrane.
- An additional lap sealer (caulking) used on the seams for a watertight seal, needs to be reapplied every 3 – 5 years.
- Uncured, more pliable rubber, is used for the detail flashing of skylights and vents and does not last half as long as the cured EPDM rubber used on the roof itself.
- Extreme heat, upwards of about 160°F, is absorbed by the black rubber membrane increasing a/c costs.
- It Punctures easily with foot traffic.
- Repair materials must be compatible with EPDM rubber.
EPDM Rubber and Seam Repairs
In the image below, this single ply EPDM commercial rubber roof failed to withstand the exposure to harmful UV rays and has had multiple seam repairs.
It has been our experience that single ply EPDM rubber roofs have their initial appeal, but over time, they are just unable to perform as promised. This roofing material has had the same inherent defects for many decades.
We feel that a true resolution for these defects lies in change. A change to a thicker membrane with UV protection and a heat fused process that melts seams together.
We specialize in such a roof system. Our TWO Ply Modified Bitumen Torch Down Rubber Roof System, is, in fact, the best roofing system to date.
The image below shows multiple repair patches on an EPDM roof. In this case, the EPDM roof surface is in fair condition; however, the adhesives used on the seams, have failed to maintain a bond and have caused leaks.
Foot Traffic Repair Patches on an EPDM Roof
The image below shows repair patches caused by foot traffic. Notice that the protective mats incorrect positioning in front of the door.