We have a concrete patio in our back yard. It's roughly 8-10 years old and i've noticed recently when looking at it at a closer level that there are hundreds if not thousands of small spots all over it.

The spots are between a rust and green color and look similar to some kind of fungus or mold. Is this common? Is this easily treatable / cleanable and if so what would i use and how often?

Thanks in advance.

 

There are commercial concrete/masonry patio cleaners available. Some contain ingredients for mold/mildew. These can be added to pressure washer which will do a very good job of cleaning patios. It's a little more difficult to do it the old-fashioned way with scrub-brush and water hose. A pressure washer will provide a deeper cleaning. Once clean, you can seal the concrete with penetrating sealer. Then, keep patio swept and hosed off as needed. Pressure wash and reseal as needed. There are services that will pressure wash for you if you do not have a pressure washer.

Mold/mildew and fungus are more of a problem on the north side of the house which gets little sun. These are also a problem where there is much shade and poor air circulation and in areas that stay damp. Pruning out overhanging tree branches will allow for more sun and air circulation.

 

Thanks for the quick reply. I will look into possibly renting a power washer at Home Depot and getting this done.

Ironically too our patio is on the south side of the house with little to no shade. Must be build up over many years of neglect..