Watch For These Common EPDM Roof Problems

2 August 2018
 Categories: , Blog

Known for its excellent durability, longevity, and energy efficiency, EPDM membranes are a common choice among contractors for commercial roof installation and restoration projects. But like every other roofing material, EPDM can experience problems over a lengthy period of time that can ultimately affect your roof's overall longevity and structural integrity.

Identifying these problems early on is essential for knowing when to replace or repair your commercial roof. Here are a few common issues to look for in your EPDM roof.

1. Shrinkage

Shrinkage is a common problem with aging EPDM roofs. EPDM can lose its elasticity over time, causing the membrane to contract and pull away from flashing and terminations. A typical EPDM roof contracts by a small percentage during its lifespan. However, this can add up to several feet of shrinkage on a large commercial roof.

The amount of shrinkage experienced by an EPDM roof depends on the methods used for installation. When mechanically attached or completely adhered to the underlayment, EPDM roofs are less likely to experience shrinkage throughout their lifetime. EPDM roofs attached via ballast often suffer the most shrinkage, usually at roof penetrations and perimeters.

2. Loose Seams

Loose seams are another common problem with EPDM roofs that can worsen as time goes on. Adhesives used to connect and seal seams between EPDM panels can dry up and fail, leaving the roof susceptible to water intrusion.

How soon an adhesive fails usually depends on the type of adhesive used for the installation. Quick seam tape is often used to connect and secure seams on ballasted EPDM installations, while glues are commonly used for adhered EPDM. EPDM seams can also come loose in the aftermath of severe weather. If winds prove strong enough to shift ballasted EPDM panels, then there's a good chance they can also pull seams apart.

A careful inspection of your EPDM roof is crucial, as even a minor gap can cause water damage to the underlayment and beyond. Most EPDM roofs require re-seaming every few years to prevent adhesion failures and water infiltration. If your EPDM roof is at the end of its working life, you may want to consider switching to another single-ply membrane that allows for seamless application. These membranes include PVC and TPO.

3. Punctures

Punctures in the EPDM roofing membrane can cause moisture to penetrate the substrate, putting the membrane at risk of adhesive failure and the underlying decking at risk of water damage and leaks. Punctures can happen when installing certain types of equipment on the roof. This is why it's important to use anchoring systems that minimize or eliminate the potential for punctures. Wearing improper footwear during a rooftop inspection can also increase chances of an EPDM puncture.

EPDM roofs should be visually inspected on a regular basis for membrane punctures and tearing. In some cases, pinholes can be found simply by looking for raindrop-sized moisture spots in the membrane. On a hot day, the sun's heat can draw moisture out of the substrate and up to the surface through the pinhole.

4. Embrittlement

Embrittlement can be an issue with older EPDM roofs that rely on uncured neoprene to cover wall flashings. Installers often used uncured neoprene due to its ability to conform to various surface shapes. With time and constant exposure to heat and sunlight, however, uncured neoprene would gradually harden and become brittle.

Uncured neoprene flashing often exhibits fine crazing during the initial stages of embrittlement. Applying a protective elastomeric coating can extend the life of uncured neoprene, but the best solution for dealing with embrittlement is to replace all of the neoprene flashing with uncured EPDM or cured EPDM with pre-molded corners and curves.

To learn more, contact a commercial roofing company like Moriarty Roofing & Sheet Metal.