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What does EPDM mean?
Ethylene Propylene Diene Monomer

Is there a warranty on EPDM?
Yes, black EPDM carries a 20 year warranty against weatherability and factory defects. Warranty excludes chalking.

Can EPDM be bonded directly over asphalt, tar, shingles, asphalt rolled roofing or felt paper?
No, the oils in pertroleum based products will cause EPDM to swell and fail. EPDM should be bonded over 5/8" plywood, 5/8" OSB board, or polyisocyanurate board with a fiberglass backing.

Can I install EPDM membrane directly over an existing roof?
You can install EPDM membrane over an existing roof only if a new layer of 5/8" plywood, 5/8" OSB board or polyisocyanurate board with a fiberglass backing is used as a barrier to protect the EPDM.

Can I bond EPDM membrane directly over plywood or OSB board surfaces?
The plywood or OSB board should be sanded to eliminate sharp edges, thoroughly cleaned, dust free and dry.

What is the temperature range for applying latex (water based) bonding adhesive?
Applying latex bonding adhesive requires an air temperature of 50 degrees Fahrenheit or above when applied. Temperature should remain above 50 degrees for at least 48 hours after application to allow the adhesive to set up. Latex bonding adhesive should be stored at 50-70 degrees Fahrenheit.

What is the temperature range for applying neoprene (solvent based) bonding adhesive?
Ambient air temperature should be 40 degrees fahrenheit or above for at least 24 hours after application. High humidity will cause adhesion problems. Never apply neoprene bonding adhesive in wet or humid conditions.

What is the coverage rate on neoprene (solvent based) bonding adhesive?
For application on plywood, OSB, polyisocyanurate board, brick, masonry or concrete: 75 sq. ft. per gallon. For application on a smooth metal surface: 100 sq. ft. per gallon

What is the coverage rate on latex (water based) bonding adhesive?
For application on plywood, OSB, or polyisocyanurate board: 125-150 sq. ft. per gallon

What EPDM thickness should I use?
45 mil EPDM is fine for most applications. However, thicker 60 or 90 mil EPDM might be preffered in applications where puncture resistance is important. For example, roof located in an area where tree limbs may fall.

Other than the EPDM, what else will I need for installation?
You will need bonding adhesive, paint roller, utility knife or scissors, push broom and we strongly recommend gloves and eye protection.

What roof slope is recommended where EPDM is installed?
For good roof drainage, we recommend 1/4" per foot.

Can I use EPDM roofing as a pondliner?
No, this is roofing grade material and is not aquatic safe. We carry a PONDGARD EPDM fishgrade liner.

Is EPDM roofing available in different colors?
EPDM is available in black and white on black. Black EPDM is very resistant to UV and ozone and has excellent sustainability and life. White on black EPDM is cooler and more energy efficient but has a shorter life than black EPDM. White on black EPDM will chalk over time. You can fin the White on Black EPDM under our RV Roofing section.

EPDM Roofing Installation

Adhering Membrane to Surface
  • Make sure that the surface is clean and dry. Remove any debris or sharp edges that may be on deck. All decking must be adequately fastened.
  • If it is not possible to clean the existing roof (e.g. - a shingle, half lap, or a gravel surface), lay a minimum 1/2" barrier board. Fasten these boards to existing deck as recommended by the fastener supplier.
  • Unfold the membrane, then lay it into position. Allow membrane to hang over roof edge approximately 3" and turn up walls 12". Allow membrane to relax 30 minutes to remove wrinkles.
  • Fold membrane back over itself, clean membrane thoroughly with recommended cleaner. Open bonding adhsesive and stir until color is uniform (about 5 minutes). Be sure membrane is in position and all wrinkles are out before applying adhesive.
  • Apply adhesive to exposed deck and to the back of the membrane. Be careful not to apply adhesive to the areas of the membrane which will later be seamed.
  • Allow adhesive to dry until it is tacky. Touch adhesive with finger. If it is still wet, wait a few more minutes. Try to avoid any thick areas or puddles of adhesive.
  • Roll the adhesive-coated membrane back onto the deck where adhesive has also been applied. Work slowly and evenly to reduce wrinkles. Use a push broom to sweep over the membrane. This will ensure proper adhesion.
  • Repeat this procedure until all of the membrane is secure.

Clean membrane thoroughly with recommended cleaner

Apply adhesive to the exposed deck

Use a push broom to sweep over the membrane


Seaming With Zip Tape
  • Overlap the two membranes to be seamed 3". Using a crayon, mark along top sheet.

Overlap the two membranes 3"
  • Fold the top sheet back about 3". Clean the seam area on both sheets with recommended cleaner. Then apply primer to both seam areas.

Clean seam area on both sheets
  • Apply 3" double sided tape along the line marked in crayon. Press tape in to ensure adhesion. The best method is to use a seam roller.

Apply Tape
  • Fold the top sheet back into place with paper backing still on zip tape. Slowly remove the paper allowing the two sheets to seam tighter. Roll seam area again to completely secure sheets together.

Slowly remove paper allowing 2 sheets to seam

Roll seam area to completely secure the 2 sheets together
  • (optional) Apply a bead of cauld to edge of the seam

Apply bead of caulk to edge of seam


Installation of Termination Bar

Some applications will require that the membrane go from a flat surfact to a 90° angle up an adjoining surface. To secure the membrane in this situation, it is recommended to use a termination bar. When adhering to the vertical wall leave about 1/2" unglued. Apply a bead of caulk between the membrane and the wall at this point. Now you are ready to fasten the term bar. When terminating on wood, screws may be used to fasten the bar. If terminating into concrete, you must drill holes and secure the bar with anchors. After the bar is in place, trim any excess membrane left above the bar. Now that the membrane is flush with the top of the bar, apply a bead of caulk along the top of the termination to finish the job. ( In corners it is recommended to cut the bar rather than bend it.)