Proflex Primer® Application Guidelines

An example of substrates that need to be coated with Proflex Primer® prior to application of EPDM Liquid Rubber® are:

• Wood

• Plywood

• Concrete

• Rigid Foams

• Previously Painted Surfaces

• Spray On Urethane Foams

When applying over the above substrates, use Proflex Primer® to stabilize the  surface. 

    The supplies you will need are:

• 1/2" electric drill

• Long shaft pail mixer

• 16-18" rubber squeegee with handle

• 9 or 12" short nap or sponge roller with handle

• rubber spatula

• 3 inch wide paint brush

• Xylene or Mineral Spirits

• Rags

Applying over Smooth Non Porous Surfaces

Smooth Aluminum, New Galvanized Steel, Glass and Plastics such as ABS, Polypropylene, PVC, Polystyrene, and Acrylic must be primed with Proflex Primer® to improve adhesion.  Hypalon and other Thermoplastic Olefin membranes must also be primed with Proflex Primer®

Spray On Urethane Foams

Since there can be considerable variations in density we recommend priming all roof foams with Proflex Primer® in order to produce a uniform surface and improve adhesion to the rubber.

Applying over Previously Painted Surfaces

Epoxy and Urethane patching products, caulks and coatings must be primed with Proflex Primer® to improve adhesion.

Applying over Porous Surfaces

When applying over porous substrates, use Proflex Primer® to stabilize the surface. 

Applying over Masonry or Concrete

With masonry / concrete, the surface to be coated must be relatively smooth (steel troweled) and uniform (not honey-combed, full of imbedded stones or aggregate breaking the surface, etc.). The surface must be structurally stable, dry, non-porous, and free of oils, debris, and flaking or loose paint. New (green) concrete should be aged 28 days.  Fill any cracks, or spalling or other surface defects on the concrete surface with Proflex Flexible Epoxy®, Butt Putty® Crack Filler Gel or ProFill® to level and smooth out the surface.  The “porosity” of concrete / masonry can be somewhat subjective and needs to be addressed prior to applying EPDM Liquid Rubber® on such surfaces. When in doubt and when time permits, prepare the surface as above and apply a 20 mils dft coat of EPDM Liquid Rubber® to a test section. Check when cured in about 4 to 10 days, for surface “bubbling” and adhesion. Bad adhesion and “bubbling” indicates that the structure is too porous. In such a case, or when testing times do not permit, it is recommended you apply a coat of Proflex Primer® on the concrete first, to “fill in the pores”, let dry, and then apply the EPDM Liquid Rubber® over the Proflex Primer® following the instructions.

The information presented herein is furnished free of charge and is based on technical data that Pro Guard believes to be reliable. It is intended for use by persons having technical skill and is at their own discretion and risk. Since conditions of use are outside our control we make no warranties, express or implied, and assume no liability in connection with any use of this information. Nothing herein is to be taken as a license to operate or a recommendation to infringe any patents.