To start with, where is the moss located on your roof? Is it beginning to block important drainage points such as gutters and downspouts? Is the moss growing in or around the gutters as well as the roof? If you notice that this is the case, then you might need to remove the moss, it could be stopping the gutters from draining efficiently which will start to create structural issues if not taken care of.
Another thing you might want to consider is the kind of materials the roof is constructed with. If roof shingles are made of stone or clay, then its unlikely that moss or this type of green growth will do any damage. However, it is a good idea to check to see if moisture, which comes from the moss, is causing either the shingles or the roofs structure to rot. If this is something you are concerned about or feel inexperienced with, then its best to consult a professional who can inspect this for you.
As always, we are here to help you with all your homes inspection needs, so please don’t hesitate to contact us for more information.