By following the simple guidelines presented here, contractors can avoid the most common driveway flaws that homeowners complain about: scaling, cracking and discoloration.
Scaling, a local flaking or peeling away of the near-surface portion of hardened concrete or mortar, has a variety of causes, the most common being exposure to freeze-thaw cycles and deicing chemicals. In cold climates, entrained air is the most important factor in reducing scaling. Finishing the slab too early or overfinishing also can lead to delamination and scaling.
To most homeowners, a crack in a driveway means the contractor did something wrong, even if the crack doesn't affect the slab's structural integrity. Crack-control measures include compacting the subgrade well and cutting or forming joints to a depth of at least one-quarter the slab thickness.
Some driveways experience discoloration problems -- dark or light patches that result in an unattractive surface. Discoloration has a variety of causes, including wet spots in the subgrade when concrete is poured, steel-troweled finishes, the use of plastic sheeting during curing and the use of calcium-chloride admixtures.