SM-1P-10-A — Aluminum-surfaced roof restoration system

SM-1P-10-A is a Western Colloid fluid-applied reinforced roof system, revised 10/20. Its classification is upgrade, smooth surface / cap sheet, 1 ply polyester reinforced, with an aluminum reflective surface. It belongs to the reinforced liquid-applied roofing systems sold as Western Cool Roof Systems.

It is a cold process method to upgrade existing roofing, including BUR and Mod Bit. The system is water based, has very low odor and uses light weight polyester fabric. The aluminum coat is a highly reflective elastomeric finish. The manufacturer's specification index lists it as a smooth cap, 1-ply polyester reinforced system using #298 Emulsion and #525 SilverWhite.

Two coats of asphalt emulsion sandwich the fabric before the aluminum coat goes on. Amounts are approximate per 100 square feet.

• Base coat: #298 Emulsion, 5 gallons, 19 pounds dry.
• Reinforcement: polyester fabric, 1 ply, 2.5 pounds.
• Top coat: #298 Emulsion, 5 gallons, 19 pounds dry.
• Reflective surface coating: SilverWhite Aluminum, 1.5 gallons, 4.5 pounds dry.

Total system dry weight is 45 pounds per 100 square feet and approximate total dry thickness is 90 mils.

#525 SilverWhite is a water based aluminum asphaltic emulsion built on #298 Emulsion with special resins and polished aluminum flake. The base is asphalt emulsion to ASTM D1227 Type III and the dried film is slightly textured with a metallic finish.

• Reflectivity: 76 percent initial (ASTM E97).
• Elongation: 166 percent (ASTM D412).
• Tensile strength: 31 psi (ASTM D412).
• Fire: non-flammable wet, Class A dry.
• Weight: about 8.5 pounds per gallon.
• Coverage: 100 square feet per gallon.
• Drying: 1 hour at 70 degrees F and 50 percent relative humidity at 100 square feet per gallon.
• Containers: 5 gallon and 55 gallon drums, and bulk.

It is recommended on metal, smooth BUR, mineral surface, emulsion and Glas Shield roof systems. It is not recommended over asphalt or wood shingles, or in roof areas with inadequate drainage.

SilverWhite performs on new asphalt emulsion once the emulsion is fully cured, which takes 3 to 10 days in warm, dry weather. New, smooth, glazed asphalt surfaces age 1 to 3 months and get a coat of #298 or #298E before the aluminum coat. Mineral surfaces first receive 2 to 3 gallons of emulsion per 100 square feet.

Spray application is the preferred method. A brush application uses a 24 inch wide soft bristle broom. Roller application is less effective. Application temperature is a minimum of 55 degrees F in the precautions, with no rain, fog or cold weather expected for 72 hours. Coating over uncured emulsion can turn the film gray, dark gray or brown.

#298 is applied by brush, roller, soft broom or squeegee at 3 gallons per 100 square feet per coat, and by spray at 3 to 6 gallons per 100 square feet. Two coats are used, the second at right angles to the first. Fabric is broomed into the wet first coat. Up to 10 percent water can be added for spraying, with the application amount raised by the same percentage.

It is odorless, contains no aromatic hydrocarbons and meets ASTM D1227 Type III and D1187. Firm set takes 12 hours at 70 degrees F and 50 percent relative humidity. Minimum application temperature is 50 degrees F. The elastomeric blend is called 298E, and the emulsion is also known as Glas-Shield Compound.

The fabric is W26/T326 at 2.75 ounce firm or T272 at 3.0 ounce soft, both stitchbonded polyester.

• WCP-HS (T272, Heavy Soft): 3 ounce per square yard, 0.025 inch thick, average tensile 57 pounds, elongation 61 percent, burst strength 176 pounds, trapezoid tear 16 pounds. Rolls are 10 square (40 inch by 324 feet) plus 4, 6, 12 and 18 inch widths.
• WCP-SF (W-26, T326, Standard Firm Finish): 2.75 ounce per square yard, 0.025 inch thick, tensile 41 pounds, elongation 25 percent, burst strength 127 pounds, trapezoid tear 14 pounds, in 10 square rolls of 40 inch by 324 feet.

The firm WCP-SF finish has fewer stitches per inch, which gives better wetability, fewer wrinkles and straighter laying on smooth or cap sheet surfaces. WCP-HS has a close knit that may need light brooming.

#800 Elastic Cement is a water based acrylic flashing, patching and sealing compound with 65 to 70 percent solids by weight, greater than 500 percent elongation and a tack free time of 1 hour. It is white or black, cures in 1 to 2 days and needs a minimum application temperature of 50 degrees F. It stays flexible below freezing.

#8000 All Weather Elastic Cement is a solvent-based white sealant for wet conditions and for setting metal flanges and sheets. It can replace #800 where a quicker resistance to water is needed.

Application takes place at a minimum of 55 degrees F and rising. It is not permitted during rain, snow or freeze, or with ice or frost on the roof surface or deck. Rain, inclement weather or temperatures below 40 degrees F forecast within 48 hours rule application out. Repair work that uses no water based material can be done just before inclement weather.

The existing membrane is repaired and made sound and watertight before application, and its fastening or adhesion is checked. Vacuuming, washing, sweeping or power blowing clears loose gravel, dirt and debris. Valleys and ponding areas are washed, optionally primed with #298 thinned 20 to 30 percent, and given an extra polyester ply in #298 before the membrane.

• Blisters: cut out and repaired by the floating patch method with modified cap sheet in asphalt flashing compound, edges at least 6 inches past the widest point.
• Large splits: the same embedded cap sheet repair, or peel and stick modified cap or APP torch applied sheet.
• Small splits: a three course method with #800 at 5 gallons per 100 square feet, one polyester ply, then 4 gallons per 100 square feet over the fabric.

The membrane starts with #298 Asphalt Emulsion at 5 gallons per 100 square feet. Full-width polyester is embedded at once, beginning at the low edge and working up the roof. Plies overlap a minimum of 3 inches, end laps a minimum of 4 inches, and the polyester ends 2 inches above the cant. The wet fabric is not walked on. After it dries, a top coat of #298 goes on at 5 gallons per 100 square feet and dries for a minimum of 24 hours.

Pipe flashings, cones, exposed metal joints and flanges then receive #800 and polyester in a three course method before the reflective coat.

• Base flashing: one ply of 6 inch (or wider) polyester in #298 at 5 gallons per 100 square feet over the cant strip, ending at least 2 inches above the cant and 2 inches onto the deck.
• Wall flashing: one full ply in #298 at 5 gallons per 100 square feet, reaching at least 3 inches onto the deck beyond the base flashing.
• Edge metal: replacement edge with low or no rise, nailed 4 inches on center, then stripped in using polyester and #800.
• Vent and pipe flanges: bedded in #8000 and nailed, with #800 excluded for setting a new flange.
• Clamping-type drains: a three course #800 or #8000 treatment of the sump, reaching 18 inches or more from the drain center, under a membrane that laps the cement by 3 inches or more.

Drains, scuppers, valleys, waterways and locations where water ponds for more than 48 hours receive an extra SilverWhite #525 application at 1.5 gallons per 100 square feet, extending 12 inches past the ponding area, before the final coat.

The final SilverWhite #525 coat covers the entire cured roof at 1.5 gallons per 100 square feet. Spray application gives the preferred result. It is applied early in the day before the emulsion surface heats and softens, after washing off asphaltic residue. SilverWhite #530 is named for roller or brush touch-up.