Cleaning the roof is necessary to maintain an optimal appearance. The key to accomplishing this is to perform preventive maintenance twice a year. During such an inspection, any problems can be identified which could, if not taken care of immediately, cause a homeowner to spend more money in the future. It is true that some roofs require less maintenance; however, all structures should be examined to be sure that they are free from debris and that all drainpipes are functional. Regular cleaning is the cost-effective way to keep a roof looking good and properly functioning. 

General Cleaning

Whether the home has a flat or angled roof, the debris that has accumulated on the surface needs to be removed. Leaves, sticks and other such things should be swept off, including from behind the pipes and pitch pans as well as the HVAC units. The collection of debris over time will stop water flow and cause deterioration particularly for asphalt roofing. Clean all gutters as well and ensure that the downspouts are in good working condition. 

To determine whether the downspout is properly functioning, water should be poured into it. Cut overhanging tree branches and if the open valley is rusty, wire brush it and apply paint. For asphalt shingles, check the caulking and sealant to see if it is damaged. Any cracks can be thoroughly scraped and polyurethane caulking reapplied.

Moss, Lichens, Mold and Algae

Moss, lichens, mold, and algae are the usual concerns for houses located in the Pacific Northwest. These organisms thrive in high humidity areas and damage the integrity of the roof by holding moisture that in turn can decrease its life expectancy. Look for the presence of these water-harboring organisms as they can damage not only the appearance but also the roofing structure itself.

Aggressive cleaning methods are highly discouraged since they can damage the composition of the roofing materials. Mosses or lichens can be gently brushed off to reduce damage to the shingles. Low-pressure washing can also be done to remove any algae colonization. Raking off moss is also possible with the help of garden hoses to wash off the debris. An oxygen bleach solution is an environmentally friendly solution that can also be applied to the surface of the housetop to get rid of an algae infestation. To prevent future growth of moss, lichens, mold and algae, a homeowner should consider installing copper or zinc strips. These strips will release a chemical compound such as zinc carbonate and copper sulfate which works to impede the future growth of algae. Additionally, trim overhanging branches that overshadow the surface as algae love shaded areas.

Keeping the housetop clean is vital to proper maintenance. Always be careful when using water while cleaning the roof, especially when removing algae or mosses as this automatically creates a slippery surface from which one can fall. Do not forget to use fall protection for safety reasons. It is also highly recommended to let a professional contractor clean the housetop. As part of a maintenance program, cleaning while conducting inspections can be done to identify problems before they occur. This will extend the service life of the roof and help to save money. Preventive maintenance is vital, so keep that roof clean all year!