Cleaning Brick Homes in Houston: Algae, Mildew, and What to Expect

By the Peak Clean team · October 13, 2026

Brick looks tough, so it's tempting to hit it with maximum pressure. But brick faces and mortar can wear down, and the wrong approach can cost you more than a dirty wall ever would.

Why brick turns green or dark

Brick and mortar are porous, so they hold moisture. Shaded sides, areas near sprinklers, and spots under leaky gutters grow algae and mildew, which show up as green, gray, or black patches.

The risk of too much pressure

• It can erode soft mortar joints and leave them recessed
• It can chip or wear the face of softer or older brick
• It can push water into the wall, where it may cause moisture problems

A safer way to clean brick

A low-pressure soft wash applies a cleaning solution that kills algae and mildew, followed by a gentle rinse. It cleans the surface without grinding away mortar or brick. Painted brick calls for even more care, so mention it when you get a quote.

What those white deposits are

If you see a powdery white film on brick, it may not be algae. It can be mineral salts that migrate to the surface as moisture passes through the wall. Those are different from organic growth, may need a different treatment, and can return if moisture is still getting in.

Fix the moisture source

• Repair or clean gutters so water doesn't run down the wall
• Aim sprinklers away from the brick
• Keep soil and mulch from piling against the wall
• Trim plants that keep the wall damp

Frequently Asked Questions

Related Services & Guides