What Are the Dangers of Power Washing Brick

Color Changes

• When you power wash a brick wall, you need to keep the water moving and avoid lingering in one spot. If you point a power-wash nozzle at a brick surface for an extended period of time, you will remove the clear coating on the brick and cause that section of brick to look different than the rest of the wall. For example, if a piece of mortar is stuck to a brick wall after construction, it is better to remove the fragment with a scraper than to try blasting it off the wall with a power washer.

Strength

• When you use a power washer on a brick wall and apply too much pressure, or use an abrasive cleaner, you will start to weaken the wall. The protective coating is removed from the wall, and the bricks begin to erode. Continuous use of a power washer to clean your brick will cause some of the bricks to start deteriorating to a point where they might crumble and weaken the wall. This could result in a partial or total wall collapse.

Mortar Stains

• If you try to power wash a brick wall without first wiping down the wall with water, the mortar will start to run. Not only does this create mortar stains on your brick that are difficult to remove, but also it weakens the mortar and can make the entire wall unstable. The mortar runs because when the cleaning solution and water are introduced to dry mortar from a power washer, the mortar quickly absorbs the water and begins to break down, according to the Masonry Work Tools website. To prevent mortar stains, use a low-pressure hose to apply water and a cleaning solution to the brick wall prior to using the power washer. Pre-soaking the mortar will prevent the water from the power washer from being absorbed by the mortar and causing stains.

Windows and Doors

• Excessive power washing around windows and doors in a brick wall will start to weaken the support structure around the window and door frame. When the brick is exposed to the elements because its protective coating has been power washed off, that brick can start to deteriorate. This can result in damage to window and door frames, such as the frames coming free from the wall.