Why Sand is Important in Sealcoating

By Kemith Nichols

Manufacturers of sealcoating materials strongly recommend adding a silica sand to the mixture. But why is sealcoating sand important? A few main reasons include:

It increases the solid content in proportion to liquid
It decreases glare from the sun
It helps prevent wear
It offers a surface more resistance to skidding

We often run into contractors who refuse to add the proper amount of sand to the sealcoating mixture. But why? Here are some common reasons:

Some contractors complain that the pump on their machine will not adequately spray the sand. This can indicate cheap equipment or inexperience.
Other sealcoat service providers argue that sand wears out their equipment faster. Even so, this should never be an excuse to cheat a customer out of the best quality product. This practice is also unethical since it adds liability to the property owner. The likelihood of automobiles skidding (and thus causing damage and/or injuries) is higher with a less skid-resistant surface lacking sand in seal coat mixture. “Slip-and-fall” incidents are also increased in asphalt seal coating that lacks proper sand content. Consider requiring your contractor to disclose and prove their spread rate and mix ratios. Asking for this data alone will often eliminate a few “fly by night” contractors.

Improper equipment agitation systems can also cause sealcoating companies to avoid proper use of sand in their mixtures. Again, this may indicate inexperience or improper equipment usage.

Not only should seal coating include sand in its mixture, the sand should meet certain criteria. First, the sand should be screened and rated 30/60 or 20/40 (these are measurements used by the US Sieve Sizes rating system). Additionally, bagged sand is preferable since it’s usually drier and measured out to allow for easier calculation of mix ratios.

The bottom line is that sand is vital in sealcoating done right. If you want an honest, knowledgeable contractor who’s more concerned with reducing your liability than adding extra life to his equipment–look no further than Exterior Maintenance Service.