For those DIY’ers who are interested in trying your hand at cleaning the green, black and grey growth off your siding, there are a few options to take.
The easiest and least expensive way is with a bristled scrub brush and a bucket of bleach. Now depending on how many stories your cleaning you may need an extension pole attachment. Be sure to dilute your store bought bleach down to about 1-2% if possible. If you start brushing your siding with full concentration the algae and mold will surely come clean but you will kill the grass and plants around the siding. A face mask/respirator should also be used to prevent damaging your lungs.
Another way you can do this which is a bit more expensive but much easier on your body is to buy or rent a pressure washer capable of “downstreaming” or adding a cleaner into the water stream. Make sure you can use a bleach product, some machines do not allow using bleach products. Mix yourself up a batch of bleach, soap (pretty much any kind of dishwasher, laundry or car wash soap will work) and water. Dilute your bleach product by 50% to start with and increase as needed.
After the cost of the purchase or rental and the hassle of getting the equipment home, set up, the project completed in a satisfactory way and returning the rental unit, you may find it easier hiring a professional for next time. Many pressure washers offer great pricing and much better quality work.