Expansive Cracking
Expansive cracking is a fairly common condition encountered in older tennis surfaces and is directly related to the expansive nature of the subsoil, degree of oxidation, atmospheric temperature variations, improper original construction and/or other causes including substrate movement or other acts of nature.

The use of various geotextile mats or membranes in conjunction with a hot plant mix asphalt overlay has been the successful method employed to bridge expansive cracking. It should be stressed that this method is NOT consistently successful. Specifically, it should be stressed that NO method employed to bridge expansive cracking is consistently successful short of removing the existing surface and correcting the cause of the problem before installing a new one.

Birdbath/Depression

When resurfacing an existing tennis court or surfacing a new asphalt court, the entire surface is flooded with water to locate all major depressions, any birdbath exceeding 1/16” or the thickness of nickel is marked and then filled with a patch mix compound. In some cases we can only reduce the amount of standing water due the existing grade or the covet's drainage.

If a depression holds more then ¾” of water, the area must be excavated and repaved of filled with a hot mix asphalt.

Birdbaths
Any areas holding enough water to cover a five cent piece (American coin) after draining a minimum of one hour at a minimum of 70 degrees Fahrenheit in sunlight, should be outlined with chalk and the water swept out. After the area is cleaned and dried, a tack coat of suitable material must be applied to the entire area within the chalk-line.

Estimate the required quantity of the thin patching mixture to fill such “birdbaths.” Apply it to the area, and strike it off with a straight-edge the length of which is in excess of the dimensions of the “birdbath.” A proper strike-off will level such a birdbath to the same elevation as the surrounding surface. After the leveling operation, the patch should be allowed to cure properly.

Fiberglass

Installing fiberglass over an existing court that is cracked, is the worse thing you can do to your court, unfortunately the only cure to repair a court that is largely cracked is to rectify the stone base or drainage & replace the existing substrate and the surface will ripple or simply crack.
When fiberglass is installed over cracks; the moisture will rise through the crack and will cause the fiberglass to separate from the substrate.

Commonly we advise tennis court owners to leave the cracks alone, unless the area has shifted and can be a hazard. Esthetically if you fill the cracks without surfacing the entire court it will look worse, thus if you fill the cracks and only patch the cracked area, it is impossible to match the existing colour and your court will look like a Picasso painting. Pictures below illustrate what happens when you use fiberglass.

Power Wash
Make sure the surface of your court is safe and free of debris.
Dirt, mold, mildew and algae can fester on a tennis court. Neglected surfaces can poses a potential safety hazard to players for slip and fall injuries. The court simply has better traction when it is clean.
It typically takes a full day to power wash one court.
Keeping your tennis court clean and free of dirt, a well as mold, mildew and algae growth helps to maintain the surface, and ensure you get the most fun out of your court possible.