Ure-A-Sil Eco

Ure-A-Sil Eco is a low-VOC, fluid-applied roof restoration system from American WeatherStar for commercial and industrial flat roofs. It is built from urethane and silicone coatings applied in layers over the existing roof surface, and it meets SCAQMD VOC requirements.

The system is used as a protective coating membrane over the entire roof surface, for spot repair, and as added protection for flashing. Its functions are waterproofing and improved energy efficiency through reflective properties. The coatings reduce the daily expansion and contraction (thermal cycling) of roofing substrates and resist dirt pick-up.

It works as a flat roof waterproofing system on six substrate types: EPDM, single-ply membrane, concrete, modified bitumen, spray polyurethane foam and built-up roofs.

The system is laid up in four steps, shown as numbered layers over the existing roof substrate.

• Surface preparation. The roof is pressure washed to remove dirt, dust, debris and other foreign contaminants.
• Seams and details. All seams and flashing details are coated with Urethane Brush-Grade 524-CA.
• Base coat. Aromatic Urethane 512-CA acts as a primer and base coat.
• Top coat. High-Solids Silicone 412 forms the top coat, giving UV protection, reflectivity and resistance to ponding water.

Aromatic Urethane 512-CA is a single-component, moisture-cure polyurethane that is topcoated with an American WeatherStar top coat. Silicone 410, High Solids Silicone 412 and Aliphatic Urethane 510 are the top coats named for it. Aliphatic Urethane 510-CA is a related moisture-cure aliphatic urethane that serves as the top coat of the Ure-A-Max system.

Separate application guidelines exist for each substrate, all titled as the Ure-A-Sil Eco roof restoration system.

• EPDM roof surfaces.
• Single-ply roof surfaces.
• Modified bitumen roof surfaces.
• Smooth and gravel built-up roof surfaces.
• Structural concrete deck roofs and other concrete surfaces.

The EPDM and single-ply guidelines state that adhesion to these substrates depends on the age and condition of each roof, and that field adhesion tests are highly recommended. On built-up roofs the component list adds a non-fibered asphalt emulsion, a cold-applied roof surface leveler. It is black, has a viscosity of 8,000 to 15,000 cps and contains 51% ± 2% solids by volume.

All system guidelines list a spunbound polyester fabric with a tensile strength of 35 psi as a reinforcing component, and EcoCleaner 925 as the surface cleaner.

Urethane Brush-Grade 524-CA is the seam and flashing coating of the system. It is a high-solids, single-component aliphatic polyurethane formulated to be monolithic, flexible and lightweight, and it reflects 80% of solar rays. It can be used on EPDM, single-ply membranes, concrete, modified bitumen, metal and polyurethane foam.

• Solids by volume: 76.7%
• Elongation: 230%
• Tensile strength: 2,300 psi
• Viscosity: 100 KU
• VOC: less than 50 g/L
• Weight: 10.49 to 10.89 lbs. per gallon
• Dry time: 12 hours at 77°F and 50% relative humidity
• Shelf life: 1 year
• Color: white
• Packaging: 3 gallons
• Clean up: acetone

It is applied by heavy brush as received. Thinning up to 10% by volume with acetone is permitted if viscosity increases. The substrate must be above 40°F and/or below 100°F, and more than 5°F above the dew point and rising. Material is stored above 40°F for cold-weather application and at a recommended 75°F in a cool area.

Aromatic Urethane 512-CA is the high-solids, single-component, moisture-cure base coat of the system. It is formulated for sealing EPDM, TPO, PVC, modified bitumen and BUR surfaces. Once cured, it is a liquid-applied membrane that resists lateral movement and shear and allows normal expansion and contraction.

• Solids by volume: 77%
• Elongation: 375%
• Tensile strength: 1000 psi
• Viscosity: 6,000 cps
• Weight: 11.7 lbs. per gallon
• Flash point: 78°F
• Hardness: 50 to 55 Shore A
• Water absorption: less than 3%
• Minimum application temperature: 40°F
• Dry-to-touch: 6 hours; tack-free: 8 to 12 hours; recoat: 12 to 16 hours
• Service temperature range: -50°F to 200°F
• Shelf life: 6 months
• Color: dark gray
• Packaging: 5 gallons and 55 gallons
• Clean up: acetone

It is applied with medium nap rollers, soft brushes or conventional airless spray equipment to clean, dry, sound surfaces. Successive coats and top coats go on within 48 hours of the base or intermediate coat. Existing coatings are checked for adhesion, and loosely adhered coating is removed before application. An adhesion test of the 512-CA base coat on the existing roof substrate is recommended.

High-Solids Silicone 412 is a ready-to-use, single-component, moisture-cure silicone coating with 92% solids by volume. It is the standard specification for liquid-applied silicone used in spray polyurethane foam roofing and single-ply restoration, and it tops several American WeatherStar systems.

• Solids by volume: 92% ± 2% (ASTM D-2697)
• Elongation: 250% ± 25%
• Tensile strength: 330 psi ± 50 psi
• Hardness: 50 ± 5 Shore A
• Initial reflectivity: 0.87 (C-1549)
• Initial emissivity: 0.89 (C-1371)
• VOC: less than 50 g/L (ASTM D-3960, EPA Method 24)
• Flash point (COC): 290°F (ASTM D-92)
• Water absorption: 2%
• Service temperature range: -40°F to 350°F
• Drying time: 1 to 4 hours
• Shelf life: 24 months
• Clean up: mineral spirits
• Packaging: 5 gallon and 50 gallon

Standard colors are white, gray and tan, and custom colors are available. The coating is mixed before application, without an electric mixer because the product is combustible. It is applied by spray, brush or roller as received, with no thinning. Subsequent coats go on within 24 hours of the prior coat. Application below 40°F is not recommended, nor when rain is expected within 1 hour; lower temperatures extend cure time.

EcoCleaner 925 is the surface cleaner of the system. It is a biodegradable, low-foaming formulation with significant renewable content, rated at 0 g/L VOC, and it meets all US VOC regulations including the Southern California regulations. At full strength it removes paints and adhesives.

• Dilution: 5:1 for most surfaces, including roof decks, concrete and steel; lower dilutions for tougher stains
• Application: low-pressure sprayer at 1 gallon per 150 sq. ft.
• Washing: power wash at a minimum of 3,000 psi with a wide fan tip, then rinse until the water is clear with no soap bubbles
• Weight: 8.3 lbs. per gallon; flash point above 212°F
• Minimum application temperature: 40°F
• Shelf life: 12 months unopened, stored between 40°F and 80°F
• Packaging: 5 gallon

The system guidelines for the individual substrates call for pressure washing at a minimum working pressure of 3,000 psi, and a range of 3000 to 4000 psi is given for the full system.

Before the system is applied, the roof is pre-inspected for needed repairs. The inspection covers HVAC flashing, drainage, drains and their locations, seams, terminations and reglets, roof penetrations, water leakage, sign or display anchorage, parapet roof detail, wet or damp insulation, and coping and flashing.

The StarGard warranty program offers 12-year, 15-year and 20-year no-dollar-limit warranty options for qualified systems installed by an American WeatherStar Approved Contractor. Each job is approved by American WeatherStar before it begins for warranty eligibility. The material warranty states that the material supplied meets or exceeds published physical properties, and the contractor guarantees workmanship free of defects in coating application.