FAQs

WHAT IS THE MAXIMUM SIZE SHEET FOR EPDM MEMBRANE?

Sheets as large as 50 feet in width are produced mostly for use in ballasted and mechanically fastened applications. Narrower widths are also produced to offer applicators greater flexibility in positioning membrane.

Narrower sheets are also produced without factory seams (seamless) for use primarily in adhered and mechanically fastened applications. The major advantage of seamless material is the elimination of factory splice T-joints that occur when factory seams intersect with field splices. This reduction in T-joints significantly increases the potential for watertight performance by eliminating potential “water channels” into field splices.

Both narrow and wide sheets are manufactured in varying lengths from 50′ to 200′.

HOW DOES THE PERFORMANCE OF EPDM MEMBRANE COMPARE TO BUILT-UP ROOFING?

Expansion and contraction, ponding, moisture, thermal shock, and temperature extremes are all factors that promote premature degradation of a roofing membrane. The great elongation and low temperature flexibility of EPDM membrane accommodate building movement in various climatic conditions without stressing the material. Its moisture absorption resistance allows the material to be installed in assemblies with lesser slope than other single-plies and makes it tolerable to incidental ponding and deflection. Unlike built-up roofing, EPDM membrane does not contain organic material that can decay as the result of moisture caused by condensation or leaks. EPDM membrane, due to its ability to withstand extreme temperature, can be successfully used in assemblies with greater thermal resistance (thicker insulations with higher R-values). The ability of a roofing membrane to withstand temperature extremes is an important trait of a high performance material because temperature extremes could promote premature membrane aging and reduce the life expectancy of a roof.

HOW CAN THE PERFORMANCE OF EPDM BE GAUGED OVER THE LAST 40 YEARS?

With over 1 billion square feet of membrane installed worldwide, EPDM has established itself as the membrane for all climatic conditions. This is supported by various laboratory studies and actual field installations. This excellent track record is the result of unique and unmatched physical characteristics:

• EPDM has superior resistance to UV (ultraviolet) radiation
• EPDM has unmatched resistance to thermal shock
• EPDM exhibits superior resistance to cyclic fatigue
• EPDM has superior resistance to hail damage
• EPDM will not become brittle and will not shatter due to low temperature flexibility

WHAT DOES EPDM LOOK LIKE?

Black EPDM has a smooth surface similar to natural gray slate and does not contain surface granules that can eventually be lost on other materials. White EPDM also has a smooth surface, but is white. It combines the high-performance standards of traditional EPDM with a highly reflective, environmentally friendly surface designed to cut energy costs. When used appropriately, usually in warm climates, white EPDM can reduce air-conditioning costs without sacrificing durability of the roofing system.

WHAT IS EPDM?

EPDM is an elastomeric compound that is manufactured from ethylene, propylene, and a small amount of diene monomer. These ingredients are synthesized to produce a product that exhibits a high degree of ozone, ultraviolet, weathering and abrasion resistance, and outstanding low temperature flexibility. These ingredients also contribute to resistance to acids, alkalis, and oxygenated solvents (i. e. , ketones, esters, and alcohols).

What applications are suitable for EPDM membrane?

EPDM membrane can be used for low and steep slope roofing, as well as unusually shaped structures (such as domes, barrels and other geometrically shaped roofs) due to its versatility. The membrane can be adhered, mechanically fastened, or loose laid. It can be installed above or below insulation (i.e., an IRMA application), and can also be used in below grade waterproofing applications.

Unlike most asphalt base products that are limited in their installation to a fully adhered application and have restrictions of ponded water, EPDM membrane can be used successfully in exposed or concealed assemblies due to its ability to withstand temperature extremes and resist the absorption of moisture.

As a vulcanized (thermoset) elastomer, how does EPDM differ from other types of single-plies (i.e. PVC, TPO, single-ply/non-vulcanized elastomer?)

EPDM membrane is a vulcanized/thermoset membrane that has been fully cured in the manufacturing process prior to shipment and delivery to the job site. With aging, EPDM membrane will not leech or emit hazardous chemicals. Unlike non-vulcanized elastomers that may begin curing in the field once exposed to moisture and heat, EPDM membrane has no shelf life. Its physical properties remain stable, which makes repairs much easier in the unlikely event of cuts or tears.