Posted on: 2 December 2016Share
Owning a commercial property comes with a variety of major expenses. Unfortunately, a failing roof can easily turn into an unplanned and unexpected expense. If you want to keep your facility in good shape and avoid the extra costs associated with emergency roof repairs and replacement, it pays to pay attention to these common signs of commercial roof failure.
Bubbling and Blistering
Bubbling and blistering often occur when moisture, usually in the form of water vapor, becomes trapped within the roof membrane. Throughout the day, constant exposure to the sun heats up the vapor underneath, causing it to expand. The resultant expansion pushes the roofing plies apart, creating a tell-tale blister or bubble in the membrane.
Bubbling and blistering are usually caused by a dampened roof environment during the initial installation or a re-cover. For instance, layering a membrane over damp substrate can trap water vapor within. Failure to protect insulation and other vulnerable materials from rain or dew can also cause eventual blistering after installation.
Brittleness and Subsequent Splitting
Whether your roof uses EPDM, thermoplastic or modified bitumen membrane, it's bound to turn brittle and lose its elasticity sooner or later. This usually happens over the course of several years, especially as constant exposure to damaging UV rays and infrared heat slowly damages the membrane. This can reduce the membrane's ability to cope with substrate movement, temperature changes and other issues that require the membrane to stretch and flex.
This issue often manifests itself in the form of long, thin cracks, especially near expansion joints and other areas where the membrane is attached to metal flashing. With the metal flashing and membrane expanding and contracting at different rates, it's possible for rips and tears to form near these areas.
Punctures and Water Intrusion
As you inspect the roof surface, there's a good chance you might see multiple tears and holes caused by previous maintenance workers and their equipment. These holes can later serve as avenues for water intrusion. The roof surface can become even more vulnerable as it ages, since the membrane no longer has the elasticity to cope with the constant use and abuse.
Water intrusion can also occur due to a combination of excessive membrane movement and loosened fasteners. Membrane movement caused by wind gusts can enlarge the hole immediately surrounding a fastener. If the fastener backs out, it can allow water to flow through the hole where the fastener once was.
Open Laps in the Field Membrane
This problem usually occurs when there wasn't enough adhesive used to properly secure the entire lap. As a result, the lap might appear properly sealed during installation, but years of wear and tear can cause it to open up, especially around the flashings. This problem can also be caused by applying adhesive to a dirty membrane or through attempted adhesion at cold temperatures.
Wrinkles in the Membrane
Believe it or not, wrinkles in the roofing membrane can also set the stage for an eventual roof failure. Wrinkles often occur due to the roof deck and perimeter moving at different rates, sometimes creating a tell-tale "fishmouth" shape near the edge of the membrane. A fishmouth can also provide a direct path for water to travel through the rest of the roof structure and into the building itself.
A loss of rooftop elasticity due to age and wear can cause the wrinkles to become "permanent," making them more vulnerable to cracking and other damage if repair efforts are made. Open cracks in the roof membrane can also allow water to directly infiltrate the underlying structure and building interior.
Looking out for these and other commercial roof problems can help prevent expensive emergency repairs and promote a more proactive approach to roof maintenance. Contact a company like Berwald Roofing Inc to address any issues.