SM-12-3G-A — Aluminum-surfaced roof restoration system

SM-12-3G-A is a Western Colloid fluid applied reinforced roof system, revised 10/20. The classification is recover, smooth surface / cap sheet, glass fiber roving reinforced, with an aluminum surface.

It is a cold process method to upgrade existing BUR and Mod Bit. This liquid-applied roofing system is water based with very low odor, and its only reinforcement is light weight fiber glass strands. The surface is a highly reflective elastomeric aluminum coating.

The manufacturer's specifications index files this system as a cap, single-ply, smooth roof system under the Glas-Shield fluid applied reinforced roof system line, with #298 Emulsion and #525 SilverWhite Aluminum as its products. The index titles the surface a glass fiber roving reinforced aluminum reflective surface.

Only three items are listed, per 100 square feet.

• Reinforced coat: #298 Emulsion, 12 gallons, 46 pounds dry.
• Chopped glass fiber roving set in the emulsion coat: 3 pounds.
• Aluminum surface coat: SilverWhite, 1.5 gallons, 4.5 pounds dry.

The dry system weighs 53.5 pounds in total and is about 108 mils thick. The assembly meets U.L. Class A.

The roving is a continuous strand fiber glass designed for use in chopped glass spray guns. It goes into the 12 gallon coat of #298 Emulsion. The materials list also names stitchbonded polyester fabric, W26/T326 at 2.75 ounce firm or T272 at 3.0 ounce soft, for reinforcing asphalt emulsion and acrylic coatings.

#525 SilverWhite is an aluminum asphaltic emulsion made from #298 Emulsion, special resins and polished aluminum flake. It dries to a flexible, elastomeric film.

• Reflectivity: 76 percent initial (ASTM E97).
• Elongation 166 percent and tensile strength 31 psi (ASTM D412).
• Dry fire rating: Class A.
• Weight: about 8.5 pounds per gallon.
• Application temperature: 50 to 100 degrees F ambient.
• Coverage: 100 square feet per gallon.

A base coat of #298 or #298E at 2 to 3 gallons per 100 square feet goes on existing mineral surfaces and cures 3 to 10 days before SilverWhite. The coating reflects up to 76 percent of the sun's rays and is suited to metal, smooth BUR, mineral surface, emulsion and Glas Shield roofs.

#298 is made from unblown soft asphalts and cures to a flexible film that does not sag, flow or re-emulsify. It resists checking and cracking. Drying time is 12 hours firm set at 70 degrees F and 50 percent relative humidity. Spray rates are 3 to 6 gallons per 100 square feet and brush rates are 3 gallons per coat.

Flexibility is tested at 32 degrees F with no cracking or flaking. Heat resistance is tested at 212 degrees F with no sag, blistering or slipping. It meets ASTM D1227 Type III and D1187 and carries 0 VOC actual and 0 regulatory.

The stitchbonded fabrics have different weights. WCP-HS (T272) is 3 ounce per square yard with 57 pounds average tensile and 16 pounds trapezoid tear. WCP-SF (W-26) is 2.75 ounce with 41 pounds tensile and 14 pounds trapezoid tear. Both measure 0.025 inch thick.

#800 Elastic Cement withstands greater stress than ordinary plastic roof cement. It is a surface flashing compound for new cold process, Glas-Shield or mineral surfaced built-up roofing, a repair compound for cold process or built-up roof systems, and a sealant for mobile home, trailer and recreational vehicle roofs. It is cleaned from wet tools with water and cures through dehydration.