Cleaning a Painted Metal Roofing System

For low maintenance, long life, amazing durability and great looks, it’s hard to beat a metal roof. About the only thing you’ll ever need to do to keep your roof in excellent shape is to clean it periodically. Here’s what you need to know about cleaning metal roofs.

What needs to be cleaned on a metal roof?

Over time, various substances can end up on your roof and mar its appearance and possibly lead to wear. These include dirt, pollen, rust, mold, mildew, pollution particles, acid rain, spore deposits and more.

By removing these substances, you’ll help to prolong the life of your roof and keep it looking good.

Metal roof cleaning supplies & tips

Important note: Before using any cleaning solution or method described here, check with the manufacturer of your roofing panels in case there are some cleaning strategies that aren’t recommended.

Cleaning a metal roof is a fairly straightforward process. Here are some guidelines to follow.

• Water from a hose and sprayer (not a power-washer) is sufficient for many cleaning tasks.
• Basic cleaning items include sponge, wash cloth, non-abrasive pad, brush with soft bristles.
• Detergents such as laundry soap (less than 5% phosphate), mild dish soap and car washing soap are all good for cleaning most metal roofs.
• A bleach-to-water ratio of 1:5 is effective in removing mold and mildew.
• Never mix bleach and ammonia together.
• Rinse thoroughly after washing so that cleaning compounds don’t remain in contact with the metal surfaces for extended periods. Depending on the size of your roof, you may want to wash and rinse one section at a time.
• Solvents such as rubbing alcohol and mineral spirits can be effective in removing tough non-water-based stains caused by oil, grease, tar and similar substances. Remember to check with your metal roof manufacturer before using these harsh cleaners.

Removing rust stains from a metal roof

In certain circumstances, rust can form on metal roofs. Usually this happens when the roof comes in contact with uncoated metal pieces and particles in the air. For mild rusting, use a non-abrasive pad and a mild abrasive cleaner applied with light pressure.

If rusting is severe, a wash cloth with solutions such as diluted hydrochloric acid, muriatic acid, vinegar, oxalic acid or citric acid can be effective. Remember four things: 1. Use only one of these solutions – do not combine them; 2. Use a ratio of 1 part solution to 5 parts water; 3. Rinse thoroughly within five minutes; 4. Check with your roof’s manufacturer first.

Don’t use these cleaning products on your metal roof

Finally, here’s what not to use to clean your metal roof:

• Paint thinner/paint remover
• Sandpaper
• Wire brush
• Scouring powder
• Steel wool
• Power-washer

Follow these guidelines to keep your metal roof looking fantastic and holding up for many years to come.

If you want to know more about the advantages of modern metal roofing, call the experts, Advanced Aluminum of Lakeland, FL, at (863) 648-5787. We manufacture the very best in metal roofing products used by leading contractors throughout the Lakeland area.