Liquid Roof Application

Temperature and Cure Conditions

Liquid Roof Application is best accomplished with a squeegee and a fine nap roller. Before applying, mix the pre-measured catalyst by following label directions. A single application is preferable to multiple coats. Touch-ups may be applied as desired after initial film has cured and surface is first wiped with solvent. To ensure its effectiveness it must be applied at a 20 mil layer. Apply with brush around flashings and edges using long, slow strokes. On flat surfaces, material can be poured, spread with a squeegee and then evened out with a short nap roller. The Product will level itself when sufficient material has been applied. Liquid EPDM Rubber Roof should not be applied on cream color ALPHA rubber. For any separation in the joints we suggest filling them with the Rutex caulk found on or order form. This Caulk has been field tested and is compatible with the liquid epdm and will not void its warranty. It is free of any solvents or isocyanates and is 100% volume solids. More information can be found HERE (RUBEX CAULK)


Adhesion will increase over time. Polar surfaces such as metal, concrete and wood result in stronger adhesion than non-polar surfaces such as asphalt and single ply EPDM sheet. Most weathered surfaces including single-ply and thermoplastic membranes will have enough of a surface profile to anchor the Liquid EPDM Rubber. Liquid EPDM Rubber Roof has proven itself superior to acrylics, urethanes, and other elastomers as a moisture barrier. Due to ultraviolet rays and weather conditions, sealants become brittle and lose adhesion, resulting in leaks. One application of Liquid EPDM Rubber Roof will provide an air and watertight seal that will outlast the original sealant.


By itself, the Liquid EPDM rubber roof membrane will exhibit the characteristics of its EPDM chemistry (i.e. U.V. and ozone stability) excellent ponding water resistance, and long-term retention of flexibility. However, since it is always applied to an existing surface, the condition of that surface will determine overall life expectancy.

Liquid EPDM Rubber applied over generally sound single ply EPDM can extend its life another 20 years. The useful life of metal roofs also benefit greatly when Liquid EPDM Rubber Roof is applied. BUR systems often have existing problems such as delaminating between layers, buckling and stress cracking. These are further aggravated by wet insulation which often results in severe corrosion and weakening of the metal supporting deck. Projecting a life expectancy for the EPDM Liquid Rubber membrane ultimately comes down to a case by case determination. When the EPDM Rubber membrane is compared to urethanes, acrylics and other elastomers in accelerated weathering and heat aging tests, the EPDM Rubber proves itself to be superior.

Liquid EPDM Roof Coatings are aftermarket products designed to extend life, seal leaks, and provide a heat reflective or aesthetic function over existing roof surfaces. Now you too can enjoy the many benefits of a weather-tight EPDM Rubber Roof. Liquid EPDM Roof is a unique form of EPDM rubber. As a liquid, it can conform to any shape of roof, flashing, or protrusion, vertical or horizontal, and can be applied easily with a paintbrush or roller on your roof.

Surface Preparation:

Surface to be coated should be clean, dry and structurally sound. Fasten loose areas with adhesive (contact cement) or pop rivets. Oil or wax MUST be completely removed with solvent otherwise the product may swell and wrinkle and will not be covered under warranty. We suggest applying one coat of the ProFlex Primer in the event you feel any oils or waxes cannot be removed. Remove loose portions of existing coatings and brittle caulk with scraper and wire brush. Whatever still has good adhesion may remain to be recoated. Rusty or pitted metal should be wire brushed to remove loose oxide. Tightly adhering corrosion may be directly coated with Liquid Roof®.

Liquid EPDM Rubber Roof may be applied on roof decks, gutters, structural steel, air conditioner enclosures, cooling towers, galvanized steel, unit heater flues, smoke stacks and chimneys, fiberglass and non-porous masonry surfaces.

Surface to be coated should be clean, dry and structurally sound. Fasten loose areas with adhesive (contact cement) or pop rivets. Oil or wax must be completely removed. Remove peeling paint and brittle caulking. Heavy build ups of asphalt roof cement should also be removed. Tighten any loose fasteners and replace those which are severely corroded. Repair or replace roof panels damaged by storms. Remove heavy rust with abrasive discs or wire brushes.

Power wash all surfaces to be coated and allow to dry thoroughly. Caulk all gaps wider than 1/16 inch which are not expansion and contraction slip surfaces.

Remove loose portions of existing coatings and brittle caulk with scraper and wire brush before using Liquid EPDM. Whatever still has good adhesion may remain to be re-coated.

Rusty or pitted metal should be wire brushed to remove loose oxide. Tightly adhering corrosion may be recoated. Asphalt based aluminum coatings should be removed as much as possible by wire brush or abrasive disc. Roof cement should be removed and replaced with butyl caulk where necessary.

Repair torn rubber by re-gluing loose areas with contact cement. Coat exposed edges with contact cement to prevent solvent absorption from Liquid EPDM Rubber Roof. A rubber patch may be applied over torn area if desired. Remove chalk from white rubber membrane by brushing with a detergent solution followed by a water rinse or working surface with a stiff brush. Smooth metal or plastic surfaces should be roughed up to improve adhesion of Liquid EPDM. A de-glossing solvent may work on some plastics.

For Large Commercial Projects: Airless or Air Atomized spraying – Airless equipment needs only one hose from pump to gun but must generate 3500-4000 psi pressure and is limited in the length of hose which can be used because of high pressure drops. Air atomized equipment requires two hoses to the gun making it more cumbersome to maneuver plus the addition of a compressor.

Applying EPDM Liquid Rubber®

Here is what you will need:


  • Electric drill (cordless drills will be effective)
  • A mixer for a can or pail.(paddle mixer) available on our order form
  • A rubber squeegee attached to a broom handle.
  • One Short nap roller approx. 1/4” attached to a broom handle.
  • Paint brush
  • Rubber spatula
  • Mineral spirits or Xylene for clean up
  • Bag of Rags

When using the broom handles it will allow you to apply the product standing up vs having to get on your knees. The paintbrush is for the corners and hard to reach sections. Broadcast the material in a letter “S” manner and then spread it using the squeegee. Follow up with the ¼” nap roller to smoothen any trapped air and equitably distribute the EPDM Liquid Rubber®. Any mistakes such as drips or platters should be cleaned off with rags. The Xylene and/or mineral spirits should only be used on the Liquid EPDM when it is still wet not to exceed 4 hours after application.

Liquid Roof is the only liquid EPDM Rubber product currently on the market.


Equipment specifications:

  • PUMP -capable of delivering 3-4 gal/min.
  • At 3500-4000 psi
  • HOSE if 3/8 inch ID max. permissible length is 150 feet
    when using .019 tip
  • if 1/2 inch ID max. permissible length is 200 feet
    when using .21 tip


Temperature and Cure Conditions

When applying liquid EPDM Rubber roof the outside temperature needs to be at least 55 degrees for cure (dry) to take place; however night temperatures or temperature drops will not affect the product, it will simply not cure until the temperature reaches 55 degrees. Liquid EPDM Roof/Liquid EPDM Rubber may be applied at any temperature that permits it being spread onto a surface. It will waterproof immediately upon application. The solvent will evaporate at a rate governed by temperature but will not be affected by relative humidity. Exposure to freezing temperatures before cure has taken place will not damage the films. The time necessary to reach cure should not be a concern as this process will occur automatically. Exposure to sunlight will accelerate the curing process. The final film properties of the cured membrane will be the same regardless of the time required to achieve cure. Liquid Roof/Liquid Rubber will provide long term protection even under extreme exposure conditions. Please read all safety precautions and heed all warnings. It will waterproof immediately upon application.


Treating Rusted Areas

It is recommended that a corrosion inhibitive primer first be applied to areas where severe rusting has occurred. Liquid EPDM Rubber does not contain any corrosion inhibiting pigments but it is such an effective moisture barrier that it may be directly applied over light rust without a primer.

Asphalt based coatings

Liquid Roof/Liquid Rubber should not be applied directly over an asphalt based coating. Water based acrylic elastomeric coatings may be used as intermediate coats before applying Liquid Roof/Liquid Rubber.

If you would like a primer solution that will allow you to use the liquid EPDM CLICK HERE.

Click Here For Elastomeric Product Information. Asphalt based applications should be considered as being unstable materials and are excluded from warranty coverage. CAUTION: Latex house paints can not be substituted in place of the acrylic elastomeric coating.


Caulking around fasteners is usually not necessary. The physical properties of the EPDM Liquid Roof/Liquid Rubber will produce a longer lasting seal around fasteners than caulks because caulks will embitter with age causing loss of adhesion and cracking.

Fabric reinforcing of seams and overlaps

Tight overlaps and standing seam joints do not need to be reinforced. Overlaps with gaps greater than 1/16 inch and corroded edges should receive fabric reinforcing. Apply a light coat of Liquid Roof/Liquid Rubber, center the fabric on the overlap and roll it out taking care not to create wrinkles; press fabric down with squeegee or wide spatula; apply a full coat of Liquid Roof/Liquid Rubber to seal top surface of fabric and roll back over to ensure coverage.

Mixing Direction:

Proper incorporation and thorough mixing of the catalyst is critical to achieving desired cured film properties and should, therefore, be done with great care. Container is filled low to allow room for mixing as well as the addition of the catalyst. Insert mixing paddle in Liquid Rubber and mix for approximately 2-3 minutes so that material is moving uniformly and has formed a vortex. Slowly add catalyst into this vortex at a rate which allows it to be incorporated without puddling. DO NOT pour catalyst on top of Liquid Rubber/Liquid Roof prior to starting mixer. After all the catalyst has been added, the mixer (if hand held) should be moved in a circular fashion around the periphery of the pail as well as up and down to insure that the catalyst is completely and uniformly mixed. Periodically scrape the sides with a rubber or metal spatula to incorporate the stagnant layer of material adhering to walls of pail.

  • Testimonials

    • Dave H.

      Overall, I am impressed with the results I obtained in using Liquid RV roof on my trailer. It was MUCH easier than replacing the membrane with new, and seems to have repaired my leaking roof, extending the life of my RV, as at some point, the cost of reroofing would exceed the RV’s value. Thanks in advance!

    • Mike H.

      My roof was in bad shape. I cleaned it and kept after it a few times a year. We bought the RV used, and there were signs of neglect when we bought it. It had been obviously sitting in the sun for an extended period of time without any care or maintenance. I was about to buy a sheet of EPDM and forego the labor intensive and very expensive task of replacing the sheet roof. Then I saw a video on Youtube for Liquid EPDM. So the research began. “This… Read more

    • Tom Pituch

      I was able to quickly find the 2 pictures I took after I patched the roof. I will continue to look for the before pictures, We have a flat roof with a channel down the middle that leads into a drain pipe system that has been our weak point area all along. Then we installed a sky light which was like adding gasoline to a fire. For years I was blaming the sky light that we installed. We even replaced portions of the sky light and sealed around it many… Read more

    • Bob & Sally H.

      The two pictures are the before and then after using your product Liquid Rubber. Very pleased with the way it turned out! And also the shipping sure came quickly. Have a great and safe day! Bob & Sally H.Yuma AZ

    • Rick M.

      The epdm rubber roof was easy to work with. I am very pleased after having a leaky roof that will be good for many years to come. Roof had mold on it so we first killed the mold with Clorox and water and scrubbed I down and then cleaned the roof with Dawn dish detergent. Attached are the before and after pictures. ThanksRick M.

  • Contact

    EPDM Coatings N.E Sales Office
    494 Bridgeport Ave Suite 101,
    PMB 342 Shelton CT 06484-4748
    Call: 610-298-1989, Fax: 702-977-2936
    Proud Distributor of Proguard Coatings
    Tel: 1-610-298-1989
    Email: [email protected]
Full Stocking Distributor of RVRoofMagic
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