Usually the first thing that makes people start to think about cleaning their roof is the look. It is somewhat underrated on most people's spring cleaning or home maintenance routine, and the truth is a lot of people do not even realize that their roof is something that needs cleaning. It definitely does though, and left untreated it can shave years off of an otherwise healthy roof in a number of ways.
Moss usually begins at the peaks, ridges, and any shady north-facing slopes, but can spread rapidly once the colony is established. It can be spread from nearby trees and sticks, animals dropping things on your roof, and high levels of moisture in the air. Heavy rains only help to incubate its growth. Left untreated, moss spreads everywhere, its roots penetrate deep into the shingles and underneath them. The roots are not the only problem, with our heavy levels of rainfall the large masses of moss trap moisture and that leads to premature rotting of the shingles themselves as the roots burrow their way beneath your shingles. On top of that, the moss can dam up valleys and gutters which leads to the potential for water backing up into the roof, clogged gutters, and water damage.
Gloeocapsa magma. What is this you ask? This is that unattractive black streaking that you will see across many roofs and it is a type of bacteria similar to algae, which will have a green tinge. On top of this being a very unattractive look for your home, it also does a few other negative things. First off, that black layer not only looks bad, but it also traps heat which makes your home's heating and cooling less efficient. That alone can raise energy bills. Next, this bacteria has an appetite for limestone in particular. Coincidentally, shingle manufacturers use limestone as a filler in the shingle-making process, handy right? While feasting on the limestone in the shingle, it breaks down the protective layer of the shingle and creates pitting, which leads to granule loss and exposes your roof to the harmful elements. This can be seen in the photo below, as you can see it typically starts at the peaks. So oftentimes even when moss is not visible but that black or green streaking is, damage is still being done.
These are only a couple of the pests in the roof world and we will look at some more, like lichens that inhabit your roof, in one of our upcoming blog posts. Stay tuned!