The quick answer is yes, power washing can degrade a concrete surface. You can notice visible damage from water pressure at the level at which even light-duty power washers can operate. Therefore, if you aren't careful, you can cause irreversible damage to your driveway or patio.
Powerful pressure washers with too much PSI will damage concrete when power washing. Most residential driveways require no more than 3000 to 3500 PSI for proper and thorough concrete washing. Heavy-duty commercial pressure washers and other power washing equipment are too strong for the average residential driveway!
Use Concrete Sealer After Power Washing
It soaks up everything! An effective pressure wash cleans the pores of your concrete. Make sure to apply concrete sealer after pressure washing.
Power washing can save your driveway from harmful growth
If you do not keep your driveway clean, it can grow algae, mold, moss, mildew – all of which can result in the need for repairs. Pressure washers do such an exceptional job of truly cleaning every pore of the driveway that mold and mildew have no chance to grow.
You absolutely should. Concrete is a very porous material and sealing it makes all the difference when it comes to its maintenance and longevity. After pressure washing your concrete driveway, it is imperative that you wait until it is completely dry before sealing it. Applying the sealer itself couldn't be simpler.
Dish soap and water: Dish soap is a degreaser, and it works well to clean oily and grimy concrete. Create a cleaning solution of warm water and few drops of dish soap and apply it to the surface. Let it sit for a while, then mop the patio and rinse it with fresh water. Repeat the process as many times as needed.
Degrease the Surface
Applying a degreaser will loosen stains in the concrete, allowing you to pressure wash them away. Some pressure washers have an attachment tool for applying degreaser. Otherwise, scrub the degreaser into the concrete with a stiff-bristled brush or push broom.
The curing process, if done correctly, typically takes around thirty days to properly dry and set to its full strength. An improper curing process, or the application of a concrete sealer before the concrete has set, can be disastrous to the longevity of the material.
How often should you pressure wash your driveway? Generally, you'll want your concrete driveway pressure washed at least once a year. This lets you treat sunbaked dirt, grime buildup, and stubborn oil stains, making regular cleaning in between professional washes much more manageable.
Medium Duty 2000-2800 PSI
They're great for cleaning concrete, brick, and wood. They work especially well for cleaning patios, sidings, roofs, decks, and fences. The medium-duty power washer is best for getting rid of stubborn stains and dirt that a low-duty pressure washer can't clean.
For instance, a light layer of dirt or dust may only require a PSI of 1,500 to 2,000, while a thick layer of oil or grease may require a PSI of 3,500 or higher to remove.
So let's find out just how much pressure it takes to crush a concrete cylinder in this science video above. Do you want to try and take a guess? The results come in at about 1:40 into the clip. The answer: a whopping 1.6 million pounds of force!
To get the job done right, you need a pressure washer rated at least 3,000 PSI with a flow rate of at least four gallons per minute (GPM).
Opt for the Most Basic Route: Soap and Water
Cleaning a concrete driveway does not have to be fancy. The easiest is the trusty soap and water mixture. Use dish soap and add it to a large bucket full of water. Then, get your stiff scrub brush, making sure it is not made of metal.
The most ideal time to pressure wash, however, is during the spring and summer months. During the warmer wetter months algae and mold will begin to grow. This is also a great time pressure wash because this is when pollen is usually at it's highest.
After the concrete has dried for at least 24 hours, you can effectively apply a concrete sealer. A sealer helps prevent future stains and potential damage from products like ice salts.
The general rule of thumb is that concrete takes about 28 days to dry for every inch of slab thickness. Within 24 to 48 hours, the concrete will be ready for foot traffic.
While pressurized water can be enough to clean your driveway, cleaning agents such as soap or detergent help loosen up all the dirt, grime, and grease. They're also great for targeting stubborn stains. Choose a cleaning agent that is specifically made for your driveway pressure washer.
Citric acid – stain removal and cleaning of concrete driveways or wooden decks. Sodium hypochlorite – disinfects and removes stains. Sodium hydroxide – dissolves grease and fats and works well on glass and steel.
We highly recommend using soap when pressure washing for more effective cleaning, faster cleaning time, and more significant results. In addition, lower pressure can be used to prevent damaging your home or equipment.
Use a detergent such as Dawn or Ajax dishwashing liquid mixed with water to brighten a concrete patio that hasn't been cleaned in a while. Use a detergent such as Dawn or Ajax dishwashing liquid mixed with water to brighten a concrete patio that hasn't been cleaned in a while.