VFI-640-1 Gray Acrylic Coating

Equipment

The coating can be applied to the surface with airless spray equipment, industrial paint brushes, or nap rollers. If spraying, use equipment like Graco Big Rig Sprayers GH 733 or GH 833 that can maintain a minimum constant pressure of 3,000 psi and are capable of 4.0 gpm. They can be used with either siphon feed or direct immersion kits. We recommend using the spray equipment with Graco Xtreme-Duty High Pressure ½-inch hoses with ¼ or ⅜-inch whip hoses and Graco Silver Plus Guns with minimum .030 tips. Another option for spraying acrylic includes the Hennes-Johnson Model 4520 Cold Process sprayer, capable of 4,500 psi at 5.0 gpm.

Surface Preparation

Using a broom, clean the entire substrate of dirt and debris that may affect adhesion. Power wash the surface as needed, and use VFI-1009 Cleaning Detergent to scrub areas with grease, oil, and animal fats. Rinse the roof of all cleaning agents and allow it to dry.

Make necessary repairs to the roof’s structural components. Gaps and seams should be tight and flush. Eliminate gaps and deflections bigger than ¼” with additional screws or rivets. Loose or backed-out fasteners must be tightened or replaced with oversized fasteners. VFI always recommends using a primer like VFI-#11 9:1 Epoxy Primer for improved adhesion.

Mixing

Mix the coating until uniform before use. Mix times may vary depending on volume and mixing method.

Application Requirements

A multicoat method using VFI-605-1 White Acrylic Coating as a top coat is recommended after applying VFI-640-1. The surface and ambient temperature must be between 50°F – 120°F and remain above 40°F during application and curing for ensured adhesion. Rain and moisture will negatively affect adhesion, so stop application if either is present.

Apply the base coat at a minimum rate of 1.25 gallons per square. A topcoat should be applied at a minimum rate of 1 gallon per square over the base coat. After topcoat application, the coverage rate should total a minimum of 2.25 gallons per square. Check specifications for required wet and dry film thickness. Apply the top coat within 48 hours of the base coat, after it has fully cured.

*Roofs with a slope less than or equal to 1/12 should be fully reinforced with polyester fabric. 

Cleaning

All application tools, including spray equipment, brushes, rollers, etc., can be cleaned with water. If the material has cured on or in the equipment, use mineral spirits.

Storage/Shelf Life

The material shelf life is 12 months from the date of manufacture. Store in a dry, temperature-controlled space in sealed and unopened containers between 60°F – 90°F. It must be protected from freezing.

Precautions

VFI-640-1 must be protected from freezing. It is not recommended for use on flat roofs or where ponding water is present. Avoid breathing in vapors or repeated skin contact. Do not thin or add foreign material to the product. See Safety Data Sheet for complete safety data.