HOME IMPROVEMENT : Upkeep Improves Driveway Mileage

From Associated Press

A concrete driveway wouldn't seem to need much care. After all, it's just a simple slab, and concrete is one of the more durable building materials. Still, driveways do deteriorate and take on a shabby appearance.

A few preventive measures you can handle yourself can go a long way in keeping your drive looking good for years to come.

One of the most obvious appearance problems is an oil spill. This is easily handled by sprinkling on cat litter. When the granules turn dark, sweep them up and apply a second sprinkling.

This time use a soft brick to grind the cat litter into the oil. You don't have to bear down too hard, just maintain a steady circular motion to achieve the best results.

When the litter is reduced to a fine powder and remains light in color, you will have removed all but a final residue that clings to the voids in the surface.

This light-colored residue will lighten further the longer it is exposed to the sun. More stubborn oil spots might require a commercial concrete cleaner or degreaser.

The adage in the concrete business is that all concrete will crack. This means that the only control the installer has is in encouraging the slab to crack in the best possible places.

While this is not completely true, as a general rule of thumb, it is a sensible way to look at concrete. Controlling the crack is done by cutting a control joint roughly every 10 feet and installing expansion joints about every 30 feet.

A control joint is merely a groove cut across a slab that is roughly one-fourth the depth of the pour. In making this cut, the installer creates a weak spot, so that crack-producing ground movement and traffic will complete the job along that line.

An expansion joint is composed of an oil-soaked fibrous material that separates one side of the slab from another.

Because it is able to expand and contract with the seasons, it allows the slab to move slightly without causing the concrete to buckle under pressure. These expansion joints are what makes the regular bumps on concrete highways and the cracks between sections of concrete sidewalks.

The problem is that this material breaks down over time much quicker than the concrete does. When this happens, the slab moves laterally, but does not move back. As such, it leaves a gap at both ends.

To keep this from happening, it is a good idea to seal the top of the expansion joint with a commercial-grade urethane caulk. You can repair a deteriorated joint and bring it back to the correct height. Clean it out and pack the settled joint with concrete backing rod (a plastic foam coil available at masonry suppliers).

Press the rod into the joint with a putty knife and cap each end of the joint with a wooden stake to keep the self-leveling caulk from running out at the ends. Then pump the top of the joint full of urethane caulk and let it flow into a level cap.

Allow a few days for the caulk to cure properly. If you must use the drive before the caulk is fully cured, lightly sprinkle sand over the joint once it starts to skin over.

This will keep the caulk from sticking to tires or your neighbor's cat.

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