Scrubbing or pressure washing a house will remove dirt and grime, but they will not necessarily remove mildew. To determine whether blackish areas are mildew or just dirt, take a little bleach and apply it to the area with a sponge.

If the black spots disappear, they are probably mildew.If they don’t go away, the discoloration is probably just dirt and should come off with a good scrubbing, using TSP or a non-phosphate detergent substitute.

To get rid of mildew, mix one part bleach to four parts water and scrub the area with the solution. Be sure to wear safety glasses and avoid getting the bleach solution on your body or your clothes. After scrubbing, rinse the area with clear water.

Depending upon the type of siding your home has, you may have an easier method: pressure washing. But beware: If your home’s paint is not sound, pressure washing may cause it to peel.

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