EPDM (ethylene propylene diene terpolymer) is commonly used on flat roofs, and it’s one of the least expensive commercial roofing options. However, your savings might just go to waste if you don’t make use of the appropriate installation method.

In this article, Roofing & More, Inc., a trusted roofing expert in Northern Virginia, discusses two methods of installing EPDM roofs: mechanically fastened and fully adhered.

Mechanically Fastened vs. Fully Adhered

Approximately 80% of EPDM roofs are mechanically fastened. It’s the more common choice for buildings due to the relatively low cost and ease of installation. However, this method of installation has its drawbacks.

Mechanically fastened EPDM roofs tend to flutter during a windy day especially if they have no secondary air barrier. This occurs because of the difference in air pressure, which pulls warm air up from inside the building through perforations or penetrations in the roof assembly. The warm air gets exposed to cooler outside air, so it needs to be reheated. This process makes the heating system work harder than it should, resulting in a 5-8% increase in heating costs.

With fully adhered EPDM, fluttering or ballooning isn’t a problem because the roof is glued directly to the insulation below. The insulation boards serve two functions: insulating and securing the roof to the metal deck. The fully adhered method is usually more expensive and slower, but it is known to make EPDM roofing more resistant to leaks and wind.

More About EPDM Roofing

There’s a reason why mechanically fastened roofs are popular among contractors and property owners. However, if your home is located in a coastal or high-wind region, you should definitely consider using the fully adhered method. In these areas, a fully adhered EPDM roof will provide better energy efficiency. To determine the right option for your building, it’s best to talk to your contractor.

Roofing & More provides an array of roofing services that meet industry standards. Call us at (703) 828-1620 or fill out our contact form to request a free quote. We offer our services to customers in Alexandria, VA, and nearby areas.