Some signs that a roof is in peril are easy enough for anyone to spot. Missing shingles, impact damage, and rusted fasteners are obvious ones, but what about those that aren’t?
A certified home inspector needs a certain affinity for detective work. Here are 4 ways you can spot a roof that’s in need of attention or might already be on its last legs.
#1: Moss in the Valleys
This has nothing to do with the landscape and everything to do with the channels that run down some roof styles. Where two sloping sections of roof intersect at the bottom edge, there’s a valley. If it’s shaded, has poor drainage or tends to collect debris, it could turn into a breeding ground for moss.
Where there’s moss, there’s roof damage. Caught early, it might be killed and cleaned off. Otherwise, moss can grow down into the spaces between shingles and can even grow underneath, lifting and breaking shingles in the process. If there’s moss, the roof needs attention. If there’s a lot of it, it might need repair or replacement.
#2: Poor Flashing Around Roof Penetrations
Everything that projects through the roof decking and shingles is a potential point of entry for water. That’s why roof penetrations need a means to divert water away and good, durable seal around them. Flashing is one of the most common ways to divert water away from chimneys, plumbing vent pipes, skylights and other objects that break through the roof.
If flashing is in bad condition, the risk of a leak if fairly high. If the sealant is also bad, it’s even higher. Where flashing and sealant are old and degraded or installed incorrectly, chances are the roof has already taken on water.
#3: Asphalt Shingle Pebbles in the Gutters
One of the sneakiest signs of a bad roof is inside the gutters. Shingles might look perfectly fine, at least from a distance. But if you spot small granules or material that looks like crumbs or pebbles in the gutters, the shingles are beginning to lose their protective coating.
Asphalt shingles begin with a durable underlayer, which the Asphalt Roofing Manufacturer’s Association says is usually fiberglass. Hot asphalt is layered over the fiberglass, which is coated with granules of minerals, which improve the shingle wear. Exposure to the elements breaks down the asphalt making it more brittle and degrading the bond between the asphalt and mineral granules.
#4: Dark, Dingy and Dirty Spots
A roof with dark and dirty spots is more than just unattractive. It might have the early signs of algae buildup. As with moss, catching algae early is important for preserving the roof. If it’s left to grow, Angie’s List says algae can hold water against the roof and ultimately ruin the shingles. If it’s left for years, a new problem—lichen—might emerge. Lichen feeds on limestone granules on the shingles and it’s difficult to eradicate.
Professional low-pressure cleaning might rid the roof of algae stains. Because there’s a risk of damaging shingles, it’s not the best project for a homeowner. In an extreme case where the algae and lichen have already taken a strong hold on the roof, replacement might be the only option.
The roof is a home’s first line of defense against the elements. It protects against the sun, wind, rain, and snow in some parts of the country. That also means it can take a beating. An asphalt shingle roof is only made to last about 20 years, depending on the quality of materials. In time, they all break down.
As a certified home inspector, you have the skills to spot an expensive and potentially damaging problem before a buyer signs on the dotted line. That helps them make an educated decision. If you’re ready to make a difference for buyers in your area, the best place to start is with a good education. Enroll now with ICA School and you could have your certification in as little as a few weeks.