Seal Coating Procedures

The sealcoat material should be coal tar based for several reasons:

1. Asphalt is a petroleum product and will be damaged by oil and gas spills. Coal tar emulsions will protect the surface.
    

2. The sun oxidizes asphalt; this is why the binder in the mix can no longer hold the aggregate in place. Coal tar does not oxidize as readily.

The sealcoat material should have at least 3 pounds of sand added per undiluted gallon of sealer to provide adequate skid resistance.

Procedure:

1. Notify tenants! A seal coating project must be properly planned since it involves taking large sections of a parking lot at a time (usually 5,000 square yards per section) and each section takes 2 days to seal and stripe. If possible, post a map with each section highlighted in a public place and send out individual notices. Make sure to explain your policy on moving cars (ie: who will pay for a tow truck)
    

2. Weather delays: Since a coal tar emulsion is water based, it must dry completely before it sets. The advent of web site weather maps has improved the process, but if rain is imminent, the sealcoat job will be delayed and tenants need to be clear about how each delay affects the scheduling of each section. The better the communication, the less chance there will be of upset tenants!
    

3. Barricade each section: The type of barricade devices is dependent on site constraints but the more obvious the better. If the barricade is easily moved or if there is a gap to fit a car through, tenants will drive through the wet material and create a mess.
    

4. Surface preparation: All dirt, vegetation and silt must be removed from the surface with blowers, scrapers or broom tractors. A sealcoat will not stick to dirt!
    

5. Taping: Tape off the entrance to get a better edge.
    

6. Primer coat (optional): If a surface is heavily oxidized, priming is recommended to maximize adhesion of the sealcoat material.