Keeping the Parking Lot Clean

Aug. 1, 1999
A few basic elements are involved in the cleaning and maintenance of parking lots and surrounding grounds. The key to a successful maintenance plan is

A few basic elements are involved in the cleaning and maintenance of parking lots and surrounding grounds. The key to a successful maintenance plan is a regular routine that reduces the overall amount of man-hours required.

That's one key. Another is the pressure washer. The following information will help your customers clean concrete or asphalt and will help your staff keep your own rental center parking lot clean.

Whether cleaning concrete or asphalt, the use of cleaning chemicals will make quicker work of removing stains and buildup of oil and grease. Many different types of cleaning chemicals are available, such as mildewcides, bleaches and degreasers. Your distributor will provide you with recommendations for your needs.

Also, to be aware of necessary precautions and to make sure there is adequate ventilation in your working area, read the manufacturer's directions carefully.

The user should utilize a blower to remove any loose debris before cleaning with the pressure washer. He should also become familiar with the different tips available and determine which would be most effective for the particular job.

High-pressure tips have two characteristics that need to be considered. The first is the orifice, which determines the amount of water that will flow through the tip. The orifice size is determined by the size of the pressure washer. The operator's manual will indicate which orifice size would be appropriate.

The second characteristic of a tip is the fan pattern, measured from 0 to 45 degrees in 5-degree increments. The fan pattern regulates how large an area the water will cover. The larger the degree tip, the larger the fan pattern. The smaller the degree tip, the more cleaning pressure the tip will provide. For example, a 15-degree tip will provide a 4- to 6-inch fan pattern when the tip is held 6 inches from the surface.

A 0-degree tip provides a straight, high-pressure stream that is typically used for difficult-to-remove stains such as chewing gum or tar. A 45-degree tip is also considered to be a chemical application tip because it provides very little pressure. Most chemicals should not be applied under pressure; the idea is to soak the surface first with the chemical and come back over it with a high-pressure tip.

The last type of tip to be familiar with is a rotating nozzle. It has a 0-degree orifice that rotates in a circular motion at high speeds under pressure. As the high-pressure stream spins, it hits the surface at many different angles, speeding up the cleaning process. By using a rotating nozzle, the user can increase the cleaning capability of the pressure washer by as much as 75 percent.


* With the chemical injector on the pressure washer, apply a cleaning solution to areas with heavy buildup of algae, fungus and mildew. The solution will help slow the re-growth of these molds, which usually occurs in damp areas with little sunlight. Other areas that will need the use of a cleaning agent are oil and grease stains. Be sure the user applies cleaning solutions that are compatible with the type of asphalt being cleaned. Check with the manufacturer if you have any questions.

* Asphalt will soften when it becomes hot, requiring the user to take precautions. A rotary nozzle or 0-degree tip can cause damage, depending on the condition of the asphalt. If there are difficult stains to be removed, the user should test a small area with the tip or nozzle he plans to use to be sure it will be safe.

* Generally a 15- or 20-degree tip will work best for most cleaning tasks on asphalt.

Concrete Concrete surfaces are very hard and require less concern when cleaning, because they do not soften when they get hot. Here are some basic steps for cleaning concrete surfaces:

* As with asphalt, the user should apply a cleaning solution with the chemical injector on the pressure washer to areas with heavy buildup of algae, fungus and mildew, as well as oil and grease stains. Be sure the user selects cleaning solutions compatible with the type of asphalt to be cleaned. If in doubt, ask your distributor or manufacturer.

* Use a 15-degree tip for most areas to be cleaned. Use a rotating nozzle or 0-degree tip on difficult-to-remove stains such as chewing gum or tar.

Preparation for striping Keeping directional markings and parking stall lines clean and painted not only improves the appearance of the area, but also plays a key role in safety. Most road markings will remain visible for nine months to a year, depending on the amount of traffic. Interior traffic markings will typically last longer, depending on the surrounding environment and the surface to which they are applied.

When preparing for re-marking, clean the areas as usual. Use a 0-degree tip or rotating nozzle to remove loose or worn marking coatings before re-coating to ensure proper adhesion of the new material.

The application of directional markings and striping of parking lots does not require a lot of manpower or experience. A few basic regulations regarding the size of parking spaces and number of handicap stalls must be provided. This information can be obtained from local municipalities.