We needed to get our siding cleaned and I’d read that pressure washing isn’t the best for vinyl siding.(can force water under the siding causing mildew & rotting). We also have an old house and were worried that water might find it’s way in with a hard pressure wash. We heard about Mildew Magic on Angie’s list and liked the sound of the cleaning method used. As it says on the website: Mildew Magic has developed the gentle fog spray machine to apply the most effective formula to destroy the living algae cells that are destroying your shingles and decreasing the value of your home. No more stains… Three year guarantee! OK, we’ll give it a try! We couldn’t believe how good it looked! The house really was quite dirty & mildew was in several spots. It looks as good as new now! He even cleaned the screens, the windows, the deck and the sidewalk! Wow! It does leave a bit of a bleach smell but it was gone in a couple days. I highly recommend Mildew Magic!