Sealcoating in Columbus, OH

Sealcoating is a thin protective coating applied over asphalt pavement. In Columbus it does three useful things: it slows the sun's oxidation that turns black asphalt gray and brittle, it helps keep water, salt brine and spilled oil from soaking into the surface, and it makes a driveway or lot look new again. It does not fill potholes, level ruts or fix a failing base. Those need repairs first, and a sealer brushed over them only hides the problem for a season.

When to seal

New asphalt needs time to cure before it is sealed; HomeGuide advises waiting three to six months after paving. After that, resealing every few years is typical. HomeGuide says to seal when it is dry and between 50 and 95 degrees, so in Central Ohio the season runs from late spring into early fall. We avoid days with rain in the forecast, because a fresh coat can wash off before it sets. Many owners like to seal in late summer, so the surface goes into winter freshly protected.

Our sealcoating steps

• Clean: the surface is blown and swept, and oil spots are treated so the sealer bonds.
• Seal cracks: cracks are filled with hot rubberized sealant first; sealer alone does not bridge a crack.
• Patch: failed areas are repaired before sealing.
• Cut in and apply: edges are done by hand and the sealer goes down in even coats.
• Cure: the area is closed off. HomeGuide puts typical cure times at 12 to 72 hours before driving, and a few hours before walking.

Sealer types

Coal tar emulsion and asphalt emulsion are the two most common sealers. HomeGuide notes that many areas have banned coal tar emulsion over health and environmental concerns, and that asphalt polymer emulsion is considered the greener choice, though gas and oil stain it more easily. We name the product we plan to use before we start.

Salt and plows

Winter salt does not dissolve asphalt the way it can scale concrete, but brine keeps the surface wet through freeze-thaw cycles and works into open cracks. A sound sealcoat and sealed cracks limit how much water gets in. Plow blades scrape sealer off high spots, so heavily plowed lots may need resealing sooner.

Is it worth it?

For a driveway in decent shape, yes. HomeGuide lists driveway sealing at roughly $1 to $2 per square foot and $400 to $800 for a 400-square-foot two-car driveway, which is small next to the cost of resurfacing or replacement. For a driveway that is already failing structurally, sealcoat is mostly cosmetic, and we will say so.