Why Do Membrane Roofs Fail at the Seams?

Why Do Membrane Roofs Fail at the Seams?

Membrane roofing failure most often begins at the seams and is the reason why roofing seams must always be included during a building’s routine maintenance inspection. Today, we take a look at the common causes of roofing seam failure.

Membrane Roofs

How Are Membrane Roofs Built?

Before we can take a look at the causes of failure, let us first discuss how membrane roofs are built. Single-ply membrane roofing features a single layer of thermoplastic polyolefin (TPO) or ethylene propylene diene monomer rubber (EPDM0 that can be installed in three ways:

  • Loose-laid, where the membrane layer is loosely laid over the substrate like a blanket and weighed down using ballast.
  • Fastened, where the membrane layer is mechanically fastened to the substrate at the seams.
  • Fully-adhered, where the membrane layer is fully adhered to the substrate using heat or adhesive.

Membrane sheets can be sealed at the seams using heat or adhesive, which can be peel-and-stick or applied separately during roofing installation.

Why Do Roof Membranes Fail at the Seams?

The most common cause of seam failure is deterioration from exposure to the elements. Adhesives can break down and lose adhesion over prolonged exposure to ultraviolet (UV) rays. Prolonged submersion, which happens when there is standing water on the roof, can also cause deterioration. While it’s difficult to determine an adhesive’s long-term performance on paper, choosing a roofing system with a proven track record can help reduce the risks of seam failure.

Poor workmanship can also lead to seam failure. Welding the seams, whether with heat or adhesive, needs to be properly done. Factors like temperature and surface coverage must be considered to avoid creating weak spots that would lead to deterioration and water infiltration. To protect your roof against damage caused by improper installation, make sure that your workmanship warranty includes coverage for it.

ABM Services & Renovations Inc provides commercial roof installation services to customers in Locust Grove and Sandy Springs, GA, as well as the surrounding communities. Give us a call at (770) 288-2368, or fill out our contact form to schedule an appointment.