Installation Guide Specification

Restoring Walls with Elastomeric Wall Coating

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I.   General

1.01    SUMMARY

  • Provide labor, materials, equipment and supervision necessary to install a spray or roller applied elastomeric acrylic wall coating system as outlined in this specification to create a seamless weatherproof coating system over masonry walls.

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


  • Submit product data sheets and literature verifying fire ratings and physical properties of materials.
  • Submit material safety data sheets.


  • Supplier Qualifications: The RENUWALL Weatherproofing System, 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 when spraying or other variables.

  • Structural cracks should be referred to the appropriate National Coatings Technical Consultant.
  • Do not apply materials unless surface to receive RENUWALL Weatherproofing System is clean and dry.

  • Install all material in strict accordance with all published safety, weather, or applicable regulations of the manufacturer and/or local, state, or federal agencies which have jurisdiction.
  • This installation guide specification assumes that the walls are structurally sound and stable.

  • 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 surface temperature is less than 50ºF. No wall coating system shall be applied if weather will not permit it to dry prior to exposure to precipitation or freezing temperatures.

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



  • The wall coating system is an acrylic, elastomeric, spray or roller applied RENUWALL Weatherproofing System, manufactured by National Coatings Corporation.
  •  The cured wall coating system shall also meet the following physical property requirements:


    Test Method


    Tensile Strength, psi

    ASTM D2370

    Minimum 325

    Initial Elongation (%)
    @ Break (75ºF)

    ASTM D2370

    Minimum 250

    Shore “A” Hardness

    ASTM D2240

    Minimum 75

    Tear Resistance

    ASTM D624

    Minimum 100

    Accelerated Weathering

    ASTM D4798
    5,000 hours

    No chalking, cracking
    or discoloration

    Wind-Driven Rain Resistance



    Permeance (perms)

    ASTM D1653

    Maximum 20

    Salt Spray, 500 Hours

    ASTM B-117

    No Effect

    Volume Solids
    Weight Solids




  • Adhesives, thinners, architectural sealants, 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.


  • For recommended spray equipment guidelines, please refer to National Coatings Technical Paper
    "TP-102 Guide for Selecting Coating Spray Equipment", or consult the spray equipment manufacturer directly.



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


  • Inspect surfaces which will receive the RENUWALL Weatherproofing System to make sure they are clean, smooth, sound, properly prepared, and free of moisture, dirt and debris.
  •  Verify that all wall penetrations, cants, and other wall items are in place and secure.

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


  • The surface must be clean, sound, dry, and free of loose mortar, chalk, oil, efflorescence, laitance, rust, loose particles and any other material that would inhibit proper adhesion of the coating. Achievement of this condition may require wire brushing, scraping, water blasting, sandblasting or other means and shall always be performed observing good trade practices.
  • Fresh concrete surfaces must be at least 30 days old prior to coating. In any case, the surface pH level must not be higher than 11 prior to coating.

  • Exterior Insulated and Finish Systems (EIFS) should be clean and free of grease and contaminants. Caulk joints should be checked, primed and resealed with ACRYFLEXÒ. Defective areas should be replaced in accordance with an EIFS manufacturer’s repair procedures.

  • Mold or mildew must be removed. Scrub surfaces with a solution of one quart household bleach to three quarts of water. Wear protective goggles and rubber gloves. Scrub well with brush and allow solution to remain on the surface for ten minutes then rinse thoroughly with clean water. Surfaces shall be pressure-washed and allowed to dry thoroughly before the application of RENUWALL Weatherproofing System.

  • All voids, holes, cracks and other surface imperfections wider than 1/16”must be clean, sound and sealed with ACRYFLEX . Allow ACRYFLEX to dry thoroughly before the application of RENUWALL.

  • Brush or roll one coat of RENUWALL into all hairline cracks.

  • All related metal work that is to receive coating shall be clean, sound and oil-free. Prime ferrous metal with RUSTSHIELD A120.


  • The entire surface shall receive the RENUWALL Weatherproofing System consisting of a minimum of 2 gallons per 100 square feet of RENUWALL, applied evenly in two separate coats as follows.
  • Using heavy napped rollers or airless spraying equipment, apply a base coat of RENUWALL at the rate of 1 gallon per 100 square feet, working the coating well into the surface. Back roll the base coat when using sprayers.

  • After the first coat has thoroughly dried, (normally 2 to 8 hours depending on temperature and humidity), apply a second coat of RENUWALL in the desired color, also at the rate of 1 gallon per 100 square feet. When spraying, use a cross hatch technique to avoid pinholes and holidays.

  • Coverage: Porosity, surface texture and specified dry film thickness will determine coverage and number of recommended coats. Over a smooth surface, coverage rates average:

1 gal/100 sq. ft =

8 mils dry

2 gal/100 sq. ft =

16 mils dry

3 gal/100 sq. ft =

24 mils dry


  • 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

  • Surfaces not intended to receive elastomeric coating materials shall be protected during the application of the system. If this protection is ineffective or not 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. RENUWALL A300 acrylic, high-performance elastomeric wall coating
  2. ACRYFLEX® acrylic architectural sealant; available as A150 trowelable grade
  3. RUSTSHIELD A120 water-based rust-inhibitive primer
  4. CLEARSEAL A101 water-based wall sealer