My Roof... should I pressure-wash it?
There are a few factors at play when considering to clean your roof. Here's a brief list of pro's and con's.
+ Remove the moss, mold, algae
+ Remove debris after storm or seasonal changes
+ Improve curb appeal
- Possibly remove cinders or asphalt (protective material) from your roof
- Potentially hazardous (proper equipment is needed)
- Roof warranties can be voided
Long story short, most roofing materials are not meant to be washed with high-pressure. Removing shingles or even just cinders can dramatically shorten the lifespan of your roof. However, if you already have heavy moss growing into your roof, that it also damaging the physical integrity of your roofing material.
However, in most cases, using an oxygenated bleach product and scrubbing or rinsing with low pressure is recommended for most algae or moss removal. Pressure-washing can be an option, but only when circumstances occur when other cleaning methods fall short.
Hope this helps - and happy cleaning!