As a surface exposed to the exterior, brick walls are vulnerable to outside elements including sun, rain, snow, mold, mildew, algae, smoke, bird droppings, sand and dust. If these are left to sit on the surface over long periods of time they will not only make such structures old and unsightly, but they will also cause material erosion. The longer you wait, the harder it becomes to remove such debris. PressureJet high pressure washers are used to eliminate water stains, salt spots, mold, mildew, dirt, wasp nests, and debris left after construction (construction cleaning).
Often times when brick and concrete are involved, the rules change. Brick companies tell you to use low pressure when washing brick. They state around 34 ? 68 bar should be sufficient enough and they also insist to never go over 103 bar ( 105 kg/cm2 / 1493 psi) If you just blast the brick wall with 344 bar ( 350 kg/cm2 / 4989 psi) you will scar up the bricks and cause a lot of damage. This is the major reason why brick cleaning jobs should be left to professionals.
Home builders are very familiar with how important it is to properly conduct post construction cleaning. A large part to pressure washing brick depends on how clean the brick layers are. If they are sloppy or if they have been laid when it has been rainy, then the brick will be smeared and harder to work with. It also matters what type of mortar was used when the walls were built. There are two main types, type N and type S. In most cases type N is used for brick and type S for block. The difference is that type N has a compressive strength of 60 bar ( 61 kg/cm2 / 870 psi) and type S has a compressive strength of 120 bar ( 122 kg/cm2 / 1740 psi) What this means is that type S does not like to come off. Make sure to ask an installation specialist what type of mortar was used originally. The next thing is the type of brick. The majority of brick are easy to clean. It is when you start getting into the sand faced brick than you have problems. The sandy surface actually gives a different kind of color than the color underneath. If you use too much pressure then the sandy finish comes off and you are left with a different color. Improper brick cleaning and pressure washing will turn red colored brick into orange-ish. Other brick soak up lots of water and are called sponge brick. What is bad about sponge brick is that no matter how much you wet down the wall you cannot keep water on the surface. In order to get the cleaning solutions to work properly they cannot be allowed to soak into the brick, they must stay on the surface. Learning how to clean brick properly is very important otherwise you could damage it.
If you are going to perform brick cleaning and pressure washing on a new building, before you start to pressure wash brick, you need to scrape the wall. These techniques are also good for after construction cleaning. You can use a metal ice scraper that has a blade on it. You need to get off all the excess mortar left on the wall. Never try to just blast it off. A general rule when cleaning brick is to pre-soak the area first and then apply BIO-Cleanse cleaning solution. Our chemicals are biodegradable liquid and are excellent for removing water stains, salt spots, molds and rust, which are very common on brick surfaces. It is absolutely safe around plants and grass, and as such, it is superior to other cleaning brands. Once the surface is wet you are ready to pressure wash. Start at the bottom of the house/wall and work across to the end of the wall, and then back to the bottom for a second run. You need to be careful with the mortar joint especially around the corners of the building since it is easy to blow them out. Never focus your pressure right on the joint. After all the dirt has been removed, rinse the entire area. If you are cleaning the wall from hard water stains you can use BIO-Cleanse. You just spray it on, watch the stain "vanish" (about 4-5 minutes, sometimes a second application is needed). Then rinse with very hot water (180ºF). Rinse the vegetation afterwards, this time with cold water, to make sure no dirt from brick cleaning settles on them. For general construction cleaning and building surface preparation we recommend diesel pressure washer or heavy duty gas pressure washer.