Copper roofing has been seen on commercial buildings for a long while now, however, residential buildings are being outfitted with copper roofing much more frequently. When you first install a copper roof, it is as shiny as a newly-minted penny. However, as time passes it dulls and will eventually turn a soft patina green.
If you don’t want to experience the inevitable changes of the coppery color, you can keep the roof clean and/or add a finishing treatment. There are many chemical products on the market that claim they can clean a copper roof to a sparkling shine. However, a homemade solution of lemon juice, white vinegar and salt works just as well if not better. You shouldn’t ever work on the roof alone. Make sure to have a friend on hand for help.
Step 1 - Mix the Solution
To mix the solution properly, you should add 3 parts lemon juice to 1 part salt. Therefore, for every 3 cups of lemon juice, you need 1 cup of salt. If you are cleaning a small copper area, a small batch may be sufficient; however, if you are cleaning an entire roof, you will need to make a large amount of the solution. If you need to make a large batch of the solution, it is best to work in a 5 gallon bucket.
Step 2 - Test the Solution
Clean debris from a small area of the roof and apply the solution. Scrub this area with your brush as you would the entire roof. This test area will give you an idea of the entire roof will turn out. If you aren’t seeing the results you imagined, add small amounts of white vinegar until you have amped up the cleaning power to your liking. Once the solutions is achieving the results you desire you can move onto the entire roof.
Step 3 - Clean the Roof
In the same manner that you scrubbed the test area, you should clean the entire roof. Use a telescopic brush for as much of the work as you can. Working on a roof is dangerous and should only be done if it is necessary. Once the telescopic brush won’t reach any higher, secure a ladder and climb to the roof. It is best to work from the top down. This will allow for the dirt and residue to flow down the roof and not contaminate the areas you have already cleaned.
As you move through the cleaning process, rinse the roof. The easiest way to do this is to use your garden hose. This will not only wash down the residue, it will also help you get an idea of how the roof is coming along.
Step 4 - Treat with Finishing Products
To maintain the coppery color of the roof, you should treat it with a clear coat sealant. These are most readily available in a polyurethane spray. Spray the roof with the sealant. Beware that as the sealant dries, the color of the roof will darken a bit.