Driveways
The main enemy of Canadian driveways is weather. Water, when it penetrates a poor surface, will eventually freeze and crack the pavement. Alternate freezing and thawing accelerates the deterioration. This happens in spring and fall, and it happens more often on a black surface, which may thaw in the sun and freeze at night despite constant cold temperatures.Water beneath the pavement is as bad as water inside it. Freezing and thawing will heave the surface. Or water may erode the soil base, leaving parts of the surface poorly supported. Design faults, such as curbs or slopes that prevent the water from draining away, exacerbate weathering effects. Or the pavement may have been designed for lighter loads than it carries.
Finally, normal wear can chew away at a surface. Oil and gasoline spots will soften and crumble an asphalt driveway. Roots from nearby trees can find their way under the pavement, breaking it up as they grow. Grass may infiltrate the edges, splitting away the surface.
Sealer will help your driveway resist liquids and remain black, but it won't protect blacktop from overloading by heavy vehicles, or prevent cracks already started from spreading. For a driveway that lasts, sealing must be combined with good maintenance and repairs.
December 4, 2008