Installation Guide Specification

Preserving EPDM RoofsLearn More About Coating Over  Aged  Single-Plies

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1.01    SUMMARY

  • Provide labor, materials, equipment and supervision necessary to install spray applied elastomeric acrylic coating system as outlined in this specification to preserve and extend the service life of EPDM single-ply roofing.

  • The manufacturer's application instructions for each product used are considered part of these specifications and should be followed at all times.


  • Submit product data sheets and literature verifying physical properties of materials.

  • Submit material safety data sheets.


  • Supplier Qualifications: The ACRYSHIELD® Roof Management System for EPDM roofs, as supplied by National Coatings Corporation, is approved for use on the project.

  • Applicator Qualifications: The applicator shall be approved by National Coatings Corporation to apply the system. Manufacturer's written verification of applicator approval is required.


  • Containers and Packaging: Deliver materials in original sealed containers, clearly marked with: manufacturer’s logo; full product name; and lot number(s).

  • Storage: Store materials between 40ºF and 100ºF with careful handling to prevent damage to products. If conditions exceed these ranges, special consideration in storage must be taken. Do not store at high temperatures in direct sunlight.

  • Protection: Protect all materials from freezing and other damage during transit, handling, storage, and installation.


  • These minimum recommendations for material usage are for ideal conditions. The number of gallons per 100 square feet may need to increase due to uneven application, rough surface texture, wind conditions while spraying and/or other variables.

  • Wet insulation must be thoroughly evaluated and then addressed with removal or other measures. Consult a National Coatings Technical Consultant regarding the need for moisture surveys and other assessments.

  • Structural cracks should be referred to the appropriate National Coatings Technical Consultant.

  • This installation guide specification assumes that the deck, if plywood, has no dry rot, and is in sound condition, or has been repaired.

  • Do not apply materials unless surface to receive acrylic roofing system is clean, dry and prepared as specified.

  • Install all material in strict accordance with all published safety, weather, or applicable regulations of the manufacturer and/or local, state, and/or federal agencies which have jurisdiction.

  • The entire system shall be fully adhered to the surface on which it is applied. Voids left under the system by creating bridges are not acceptable.

  • Do not proceed with application of coating or sealing materials when temperature is less than 50ºF. No coating system shall be applied if weather will not permit it to dry prior to exposure to precipitation or freezing.

  • Heavy puddles of coating on the roof are not acceptable.

  • Instructions for use of all roofing materials and application equipment should be read and followed at all times.

  • As a general principle, to prevent the ponding of water, install additional drains as necessary.


  • This specification does not extensively outline procedures for preparation and finishing of drains, vents, ducts, flashings, parapet walls, sheet metal work, etc. This work should be outlined by the contractor before work commences, and shall be performed observing good trade practices.



  • The roofing system is an acrylic, elastomeric, spray-applied ACRYSHIELD Roof Management System manufactured by National Coatings Corporation.

  • Physical Properties of Cured Roofing System: The testing of the coating shall be done under ASTM-D6083, “Standard Specification for Liquid Applied Acrylic Coating Used in Roofing”, unless otherwise specified.

  • The roofing system shall have good resistance to ponding water.

  • The roofing system shall contain no plasticizers.

  • The roofing system shall contain no migrating fire retardants.

  • The roofing system shall have a Class A fire rating on a noncombustible deck when tested according to the procedures outlined in ASTM E-108.

  • The top coat shall also meet the following physical property requirements:


    ASTM Method


    Tensile Strength, psi (Max @ 73ºF)


    Minimum 250

    % Elongation @ Break (73ºF)


    Minimum 250

    Permeance, perms


    Maximum 15

    Volume Solids %
    Weight Solids %


    > 50
    > 6

  • The reinforcing fabric shall be Tietex T272 or an equivalent that meets the following physical property requirements:


    Test Method

    Average Value




    Weight (per sq. yard)

    Calculated by formula

    3 ounces

    Bursting Strength (lbs)

    ASTM D3786


    Tensile Strength (psi)

    ASTM D1682


    Tear Strength (lbs)

    ASTM D1117


    Elongation (%)

    ASTM D1682





    Ease of Saturation




  • Flashing, adhesives, thinners, elastomeric caulking compounds, primers, and similar materials shall be approved by the manufacturer of the coatings. All materials used shall be applied in accordance with its manufacturer's recommendations.




  • Compliance: Comply with manufacturer’s product data, including product technical bulletins and product guide specification instructions.


  • Inspect surfaces which will receive the ACRYSHIELD Roof Management System to make sure they are clean, smooth, sound, properly prepared, and free of moisture, dirt, debris, or other contamination.

  • Verify that all roof penetrations, mechanical equipment, cants, edge metal, and other on-roof items are in place and secure.

  • Verify that all critical areas around the immediate vicinity of the spray area are suitably protected.

  • Verify all roof drains are clean and in working order.

  • Verify that all air conditioning and air intake vents are suitably protected or closed.


  • The surface must be clean, sound, dry and free of any materials that would inhibit proper adhesion of the coating or sealant. Achievement of this condition may require the use of INDUSTRIAL CLEANER, scraping, power brooming, vacuuming or other means, and shall always be performed observing responsible trade practices.

  • Pressure-wash the membrane free of any significant accumulation of dirt and debris prior to applying the base coat. Where unsealed membrane or seam defects are discovered, avoid introducing water beneath the membrane by using lower pressure and/or manual rinse techniques.

  • All loose seams of existing roof system shall be sealed in accordance with the EPDM manufacturer’s recommendations. Then seal all EPDM single ply seams with BUTYL SEAM TAPE.

  • Seal all HVAC duct work joints as needed with ACRYFLEX® and reinforcing polyester fabric or BUTYL SEAM TAPE.

  • Surface must be entirely clean before proceeding with application of base coat.

  • Thoroughly clean areas immediately surrounding loose seams or membrane punctures and defects, then seal such areas in accordance following the EPDM manufacturer recommendations.

  • When specified by the coating manufacturer, reinforce seams using either BUTYL SEAM TAPE or ACRYSHIELD® A502 coating and 10” wide T272 polyester reinforcing fabric. Fabric shall be totally saturated with approximately 3 gallons per 100 squares of coating.

  • Reinforce around skylights, equipment platforms and other roof penetrations using 20” wide T272 fabric and ACRYSHIELD A502 coating. Extend the reinforcing fabric several inches up onto the skylight, etc. edge and then down onto the surrounding roof field. Use approximately 3 gallons per 100 square feet to fully saturate the reinforcing fabric. Avoid air pockets and so called “fish-mouths” in the fabric reinforcement.

  • Reseal around mechanical equipment, coping seams and other critical junctures using ACRYFLEX® architectural sealant and, where possible, T272 reinforcing fabric.

  • Remove seam fasteners that are backing out and install new inter-locking mechanical fasteners with seam plates.

  • In all valley areas, waterways, drain areas or other areas where potential water accumulation is a concern, apply ACRYSHIELD A502 at the rate of 2 gallons per 100 square feet, approximately 46 inches wide. Immediately embed 40 inch wide T272 polyester reinforcing fabric into the wet coating, with a second coat of ACRYSHIELD A502 being immediately applied on top of the fabric at the rate of 1 gallon per 100 square feet. Both the first and second coats shall extend a minimum of 2 inches beyond the edges of the polyester reinforcing fabric. In any large valley area multiple widths of fabric should be used, overlapping them a minimum of 3 inches so that the coating and fabric extend at least six inches up above the potential waterline.

  • Allow coating to dry thoroughly (normally 8 to 24 hours depending on weather conditions), before proceeding to application of the remainder of the roofing system as described in section 3.04 of this guide specification.

  • Seal all HVAC duct work joints as needed with ACRYFLEX and reinforcing polyester fabric or BUTYL SEAM TAPE. Coat entire duct assembly with two 1½ gallon coats of ACRYSHIELD A500.


  • Following the surface cleaning, defect repair and custom reinforcing detailed in Section 3.03; the entire roof shall receive the ACRYSHIELD Roof Management System consisting of a minimum of 24 dry mils of ACRYSHIELD coating or approximately 3 gallons per 100 square feet.

  • Apply a base coat of ACRYSHIELD A502 coating by spray or roller at a rate of 1.5 gallon per 100 square feet. Allow to thoroughly dry for normally 8 to 12 hours depending on weather conditions.

  • Apply a top coat of ACRYSHIELD A500 coating in a cross-hatch technique at a rate of 1.5 gallon per 100 square feet. Allow to thoroughly dry before exposing to foot traffic.

  • All coating edges shall be cut evenly in a uniform manner so as to provide an aesthetically pleasing appearance.


  • In case of manufacturer’s labor and material warranty - Manufacturer’s Field Services: Inspection by the coating manufacturer's representative shall be made to verify the proper installation of the system. Any areas that do not meet the minimum standards for application as specified herein shall be corrected at the contractor's expense. Manufacturer's inspection or verification shall not constitute acceptance of responsibility for any improper application of material.

3.06    CLEANING

  1. Surfaces not intended to receive the ACRYSHIELD Roof Management System shall be protected during the application of the system. Should this protection not be effective, or not be provided, the respective surfaces shall be restored to their proper conditions by cleaning, repairing or replacing. All debris from completion of work shall be completely removed from the project site.


The following materials listed in these recommendations are available from National Coatings Corporation:

  1. ACRYSHIELD® A502 acrylic, elastomeric basecoat for EPDM roofing membranes.

  2. ACRYSHIELD® A500 acrylic, elastomeric roof coating.

  3. ACRYFLEX® acrylic architectural sealant; available as A150 trowelable grade.

  4. BUTYL SEAM TAPE polyester-reinforced waterproofing tape.

  5. T272 polyester reinforcing fabric, 6-inch, 10-inch, 20-inch and 40-inch.

  6. INDUSTRIAL CLEANER water-based, biodegradable cleaner.


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