Aromatic Urethane 508
Designed for commercial roof restoration applications, Aromatic Urethane 508 is a high-solids, single-component, moisture-cure polyurethane base coat. Its elastomeric formulation creates a seamless, flexible, and weather-resistant membrane that resists lateral movement, shear stress, and thermal cycling for long-term performance. Intended for use over EPDM, TPO, PVC, Modified Bitumen, and BUR surfaces, it must be top coated with an approved American WeatherStar finish coat such as Silicone 410, High Solids Silicone 412, or Aliphatic Urethane 510.
- Superior adhesive and cohesive strength
- Forms a durable, seamless waterproof membrane
- Excellent elongation and tensile strength
- Resists weathering and environmental stress
- Accommodates thermal movement and substrate expansion
- Flexible elastomeric coating for long-term performance
- Compatible with multiple commercial roofing substrates
- Solids by Volume
- 70% ± 2%
- Elongation
- 475% ± 50%
- Tensile Strength
- 725 ± 50 psi
- Viscosity
- 6,000 ± 2,000 cps
- Weight per Gallon
- 8.90 ± 0.1 lbs per gallon
- Flash Point
- 80° F
- Hardness
- 65, Shore A
- Permeability
- .02 perms
- Water Absorption
- 2.4%
- Minimum Application Temperature
- 40°F
- Dry Time
- Dry-to-touch: 6 hours, Tack-free: 8-12 hours, Recoat: 12-16 hours
- Service Temperature
- -50° to 200°F
- Clean Up
- Xylene and/or Acetone
- Modified bitumen
- Metal
- TPO
- PVC
- EPDM
- Spray polyurethane foam
- Smooth built-up roofing
- Surface Preparation
Pressure wash the roof (2,500–3,500 psi) to remove dirt, debris, grease, mildew, and loose material. Ensure the surface is completely dry for proper adhesion.
Inspect and repair damaged areas. A primer may be required based on substrate age and condition.
- Mixing/Thinning
Mix thoroughly with a drill mixer for ~3 minutes for uniform consistency. If needed, thin up to 10% (1:10 ratio). Consult Technical Services for specific guidance.
- Application Methods
Apply using an airless hydraulic sprayer or a medium nap roller.
- Coverage Rates
Dries to the touch in 2–4 hours under normal conditions. Apply additional coats within 24–48 hours. Full cure occurs in 7–10 days, depending on temperature and humidity.
- Limitations/Precautions
Do not apply if surface temperature is below 40°F, as it may hinder curing. In cold weather, store indoors until use.
High humidity speeds curing; low humidity slows it. Avoid application if rain is imminent to prevent adhesion issues.
- Storage/Handling
Store in a cool, dry place, away from sunlight and heat. Keep containers sealed to prevent moisture exposure and premature curing.
While freezing rarely causes damage, extreme temperature fluctuations can affect consistency. Store in controlled conditions to prevent freezing.
- Cleanup/Disposal
Clean tools and equipment immediately after use with an appropriate solvent. Dried material may require mechanical removal.
Do not dispose of liquid material in drains or waterways. Follow local, state, and federal regulations for proper disposal of unused product and empty containers.
