Get matched with top sonic cleaning pros in Dayton, MD

Chemical herbicides will kill moss permanently. The same goes with bleach water. However, moss can start growing again once a new layer of dirt and debris is caught in your sand in paver joints. Therefore, the problem is not about killing moss permanently, but ensuring effective prevention of moss regrowth.

The cost depends on roof size, pitch, accessibility, and contamination extent. A steep roof or extensive moss growth may raise the price.

Flat roofs are a solid option for people who want extra outdoor space. Flat roofs are very common in other parts of the world and only recently has the U.S. started to see the benefit in the increased space. Flat roofs are also easier to maintain and pose much less of a safety risk, which allows for more DIY work for handy homeowners. Some people also build green or living roofs that grow plant life. 

The best time of year for roof cleaning depends on your local climate, but generally, late spring, summer, or early autumn are ideal. Plan to clean your roof on a day with dry weather and moderate temperatures.

Late spring and early summer are excellent for cleaning off grime accumulated after a snowy winter or wet spring. Summer often provides the necessary dry conditions, though in very hot climates, late spring may be more comfortable. Alternatively, cleaning in late autumn can clear away debris like leaves and branches before winter.

Avoid cleaning your roof when it is cold enough for water to freeze, as this can cause dangerous ice buildup.