Your home’s roof and gutters are designed to shed water off your house and away from it. Your roof suffers wear and tear from the sun, rain, wind, falling debris , birds, algae, and moss. Regular maintenance will prolong the life of your roof, move water away from the house where it can do damage, stop organic growths that damage roofing materials and give your roof an appearance that will enhance the curb appeal of your home.
The most important roof maintenance item is keeping your gutters clean and downspouts unclogged. When your gutters get full of organic materials, water is retained in the gutter with all the other organic materials. If this gets deep enough to reach the top of the gutter, it can wick or migrate back up into the roof sheathing that makes up your soffit. If this is a chronic problem, the soffit roof sheathing will begin to rot. This can create a very expensive repair job. The weight of full gutters will also begin to cause the gutters to sag or pull away from their attachment points on the house facia and rafter tails, this can lead to low spots that pool water, water falls over the side of the gutter, and the gutters eventually falling off.
Downspouts need to also be kept open and clear. The entry hole in the gutter needs to be kept clear, the bends or elbows in each downspout, and each section needs to be fitted tightly to the next to stop drips or leaks. The downspout should empty into a perimeter draining system that takes water away from the house or it should exit out an elbow and extension at the ground that directs water away from the foundation. Splash plates of also used to direct water away from the foundation. It is vital that the grade and slope of these extensions run water away from the foundation and not toward it.
Your roof surface, any valleys, any flashed areas, skylights, chimneys, vents, plumber vents, or mounted items all need to be cleaned of organic materials that might collect and block or misdirect proper flow of water from the roof to the gutters, A blower can work great for this but it is vital that you only blow from the up hill side toward the downhill side of your roofing material. You do not want to blow air up under the shingles or you could damage your roof.
Your roof will also grow a variety of fungus, algae, and moss materials. This is more often seen in shady areas and on the north facing roof areas. It is important to treat this annually to stop extensive growth that can damage your roof. There are liquid products that can be sprayed on your roof from a pump sprayer or powdered products that you sprinkle on each side of the roof near the ridge cap. If evenly distributed and not laid down too thick, this product will melt and run down roofing material the first time it rains after it is applied. This should kill moss and algae. You might have to apply this several times to get it all depending on how bad your roof is. On a dry day the dead treated material can be brushed lightly and removed. Never use a pressure washer or a high-pressure hose on asphalt composition roofs. This will age your roof by washing off granules that are embedded in the tar material in the shingle
Zinc strips can be installed near the ridge that are supposed to kill moss but these lose their ability to do so after a few years in use. The less you walk on your roof the better and especially during hot summer days when the roofing material is very hot and soft.
Membrane, torch down, and hot tar roofing is generally seen on flatter roofs where there is not enough slope to drain water over shingles. These require regular cleaning like normal roofs and the water drainage systems need to be maintained as well.
If you discover damaged, missing, or folded back shingles it is important to repair these areas as soon as possible. Unless you know what you are doing, I recommend you have a professional roofer make the repairs.
Always remember that the goal is to clear all loose organic matter, treat and remove all moss and algae, keep all flashings clear of debris and growths, keep gutters open and clear, keep downspouts open, and to give water a clear pathway to drain down and away from the house.