Metal Acrylic

Metal Acrylic is a Kool Coats coating system for existing metal roofs that uses a rust-converting primer, a sprayable rubber for seams and fasteners, and an acrylic topcoat. It belongs to the Metal family and is listed for the USA market.

Profiled metal panels meet at side laps and end laps, and exposed-fastener roofs, including R-panel roofs, carry washers and screws. In this system the flexible rubber layer handles those details, and the acrylic coats the exposed surface.

It is one of the metal roof restoration systems in the Kool Coats range, and its acrylic chemistry is the counterpart to the silicone metal system.

Three Kool Coats products are used.

• P-309 Rust Converting Primer for rusted metal.
• TS-400 KwikShot Rubber sprayable seam prep for seams, fasteners and transitions.
• TS-505 TopShot EDGE acrylic topcoat for the field.

The roof is cleaned first, and gaps, cracks and areas larger than 1/8 inch are identified. Larger gaps are filled with KwikShot caulking grade. KwikShot is then sprayed across seams and detail areas, and a reflective acrylic topcoat finishes the roof. Seams, screws and movement points are sealed in one pass, with no embedded fabric.

KwikShot is rated at 30 mils dry film thickness and 1200% elongation, with membrane strength up to 1,540 psi.

P-309 converts red hematite rust into black magnetite, leaving a hard surface for coating. Because the carrier is acidic, with a nominal pH of 4, the converted surface is rinsed with clean water and allowed to dry before an acrylic coating goes on, which prevents discoloration from residual acidity.

Metal showing active red rust receives it after loose rust, scale, flaking paint, grease and oil are removed. It is not applied over galvanized, painted or non-rusted metal. It goes on between 50 F and 120 F and rising, at 0.25 to 0.5 gallon per 100 sq ft at 4 mils wet film thickness, and conversion takes about 24 hours at 77 F and 50% relative humidity.

• Weight per gallon: 8.8 lbs; viscosity: 65 KU
• Solids by weight: 48% nominal
• Color: clear white
• Packaging: tote, drum, 5 gallon, 1 gallon and 12 x 1 quart

KwikShot TS-400 is a water-based, non-silicone liquid rubber sprayed on seams, laps, fasteners, flashings and transitions in commercial acrylic and urethane roof systems, without fabric. Listed performance is 100% waterproofing at 30 mils dry film thickness and up to 1200% elongation. The coverage rate is 1 gallon per 100 sq ft at 30 mils wet film thickness.

Application is between 50 F and 90 F on a warm dry surface at least 5 F above the dew point. Brushes and rollers (3/8 inch to 1/2 inch nap) are nylon or polyester, and spraying uses airless equipment between a minimum of 0.015 tip, 0.34 GPM and 3,000 psi and a maximum of 0.065 tip, 4.0 GPM and 4,000 psi. A test patch is made to check adhesion. For exterior vertical wall exposures it is topcoated with a Kool Coats acrylic or urethane coating.

TS-505 TopShot EDGE is an elastomeric acrylic with reduced filler content, listed for 15-plus year systems and for high-build, one-pass commercial restorations.

• Solids by volume: 52%; by weight: 62%
• Weight per gallon: 10.8 lbs
• Tensile strength: 300 psi; elongation: 360% nominal
• Tear resistance: 105 lbs/in; hardness: 65 Shore A
• Application temperature: 50 F to 100 F
• Cure time: 24 to 48 hours at 77 F and 50% humidity
• Service temperature of the cured film: 15 F to 180 F
• VOC: less than 50 g/L

It is applied by airless equipment capable of 2000 to 3000 psi or a medium nap roller, with a brush for touch-up. It is mixed to uniform color and not thinned. Application is not recommended below 40 F or with rain expected within four hours. Drying takes 1 to 4 hours.

TopShot tools are cleaned with water, or lukewarm water and soap followed by an isopropanol, acetone or Simple Green rinse. Mineral spirits, xylene, toluene, and VMP and naphtha are not used. TopShot has a 12-month shelf life; P-309 has two years. A 10 to 20 year Kool Coats Material Warranty, with a Labor and Material Warranty available for a fee.