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Why is my siding turning green?

If one side of your house has turned green, you’re not alone. It’s one of the most common things we see around Zanesville, and the good news is it comes off.

It’s algae (and sometimes mildew)

That green or gray-green film is almost always algae. It’s a living thing, and it grows on siding the same way it grows on a rock in a creek: it needs moisture, a little light, and something to hang on to. Black spots or a dingy gray film are often mildew or mold mixed in.

Why it’s worse on one side

You’ll usually see it heaviest on the north side of the house, under trees, or anywhere that stays shaded and damp. Those spots don’t get enough sun to dry out after rain or morning dew, so the algae gets a head start. Ohio’s humid summers help it along.

Why it keeps coming back

Spraying it off with a garden hose or a rented pressure washer knocks down what you can see, but it doesn’t kill what’s left in the texture of the siding. That’s why it’s back in a season or two.

How to actually get rid of it

A soft wash uses low pressure plus a cleaning solution that kills the algae at the root instead of just blasting the top layer off. It’s gentler on your siding and the results last longer.

To keep it from coming back, wash it regularly. That’s exactly why we offer the Keep It Clean Plan: your first wash is $299, then $249 every six months, so the green never gets a chance to build up again.

Is it hurting my house?

Algae on vinyl is mostly a looks problem, but left alone for years it can stain, hold moisture against your home, and make the whole house look older than it is. Cleaning it off is a lot cheaper than the curb appeal it costs you.