There are a variety of methods that are implied in order to do concrete cleaning. The methods differ based on whether concrete sealing has been done on it using concrete sealer, and what kind of cleaning is required, among other criterion. But, generally, there are three main methods that are used. They are explained below -
Water Washing – Water washing simply consists of using a garden hose connected to a tank or any water source. Along with that detergent and cleansing chemicals have to be used. As the water here is used at a low pressure (about 15 to 30 psi) it is also known as low pressure water washing. To remove stains, scrubbers, brooms or mops might have to be used. A concrete sealer would of helped here preventing stains from penetrating.
Pressure Washing – Pressure washing includes using water at a higher pressure in order to force the stains to dislodge from their place. It uses about half of the water compared to water washing, but uses high pressure. The pressure used is 1,450 psi for domestic pressure washer machines, and ranges from 2000 to 6000 psi for professional or factory pressure washers. A fan nozzle is generally used to cover wide areas, while a point nozzle maybe used to concentrate on small areas with specific dirt spots. Usually water is enough to remove stains, since the high pressure does the work, but sometimes mild detergents have to be used. Care must be taken since a concrete sealer can be stripped here if too much force is exerted.
Steam Washing – It uses the highest amount of pressure amongst all the three methods. The high temperature that can be used with steam washing helps to clean off algae, fungi and bacterial accumulation, and is fit for hotels, hospitals and cafeterias where food is frequently cooked, and the cleanliness level has to be constantly maintained. To clean concrete surfaces only with steam cleaning, can be a slow process however, and is generally used along with pressure washing. Chemicals that are recommended by the manufacturer can be used to remove contamination. However, the surface must be rinsed with clean water after steam washing has been done.
Out of the three methods, Pressure washing is the best. It saves you time, energy as well as resource. As stated above, it requires half the amount of water compared to water washing. Even steam washing is not enough, and has to be used in conjugation with pressure cleaning. With Pressure washing, you do not have to scrub off the stains; the pressure of the water itself is enough. If a concrete sealer was originally applied then most of the times, there is no need for detergent or cleansers.
Although, if you want to use cleansers, go through the owner’s manual and make sure that your machine can handle it. If you do not clean regularly, and therefore are not sure whether to buy a pressure washer or not, you can always rent one. If you are comfortable, you can go ahead and buy. Whether you buy or rent, do adequate research before selecting a particular machine. If you feel you can’t handle the washer or have any difficulties in concrete cleaning, you can always call professionals to do the cleaning for you.