Slate Roof Maintenance

Unscrupulous roofing contractors who don't specialize in slate might take advantage of your worry. They'll try to convince you that your roof is beyond its service life and absolutely needs to be replaced, probably with a space-age composite product they happen to have on hand. They'll go on to explain that practically nobody works on slate anymore and that modern chemistry has perfected the slate look-alike.

This is predatory, gives roofing contractors at large a bad reputation as ruthless profit seekers, and is plainly untrue. But you knew that or you wouldn't be here.

In general, slate roofs can be repaired rather than replaced. Except when they're at the end of their immense service life or something unusually catastrophic has happened. A well maintained slate roof on an equally well-maintained home can last a very long time, a century or longer. For some especially robust types of slate, two centuries or more is typical. This is no lab experiment. It's stone. 

The stuff lasts.

But that maintenance part is essential. A roof is a system, comprised of inter-connected parts, each with their own service lives and points of potential failure. To this end, we suggest to all of our customers to have an annual inspection. This is key for two reasons: it will let you know if any damage occurred throughout the winter and it will keep you ahead of any major repairs. This makes for easy budgeting. Being proactive about your roof is the best way to save money. You always want to make a repair before it leaks. 

Why spend the extra money on interior repairs, too?

Now, let’s start with the most basic repair – the slate. You are bound to have broken and slipped slates from time to time, especially if you have large trees around your home or there has been a strong storm. Slates can be individually repaired easily by a trained slater. Small, chipped corners on slate may look ugly but will not cause a leak. You will want to keep an eye out for missing or badly broken slates.

The next type of repair is the flashings. Flashings are the metal you see around the base of the chimney, the soil stacks and other protrusions, at the ridge and on hips, and in the valleys. These are commonly copper or galvanized steel on a slate roof. Copper flashings have a service life of about 70 years and are maintenance free. Copper will patina naturally in the elements and turn a dark brown then the rich green that we all have seen. The green color lets you know that it is getting older but still has service life left in it. When copper turns black then you know that time is ticking. Galvanized flashings will last 15-20 years and need to be kept painted or they will rust very quickly. While galvanized flashings may be more economical for you if you need a repair, keep in mind that they will require regular painting and over the long run may not be any less than copper.

Chimneys can be a complete headache for a homeowner (and a roofer too!) if not maintained. You have to consider the chimney itself, the masonry, the flashing, and the cap or flue covers. These different parts all have their own job in keeping water out of your home. Chimneys can be very tricky because there are actually nine different causes for a chimney leak. Inspecting the flashing to make sure it is still in good condition, checking the bricks and joints for any missing mortar, and verifying that chimney is properly lined if it is used to vent a furnace are very good ways to guard against leaks.

The final aspect of your roof that you will want to keep in good working order is your gutters and downspouts. You either have box gutters or hanging gutters and each have their own maintenance needs. Box gutters are built into the rafter system of your roof and from the ground simply look like decorative wood molding around the perimeter of your home. The trough of the gutter is lined with metal, either copper or galvanized. As with flashings, if your gutters are galvanized they will need regular painting. Hanging gutters are attached to the eaves of your home using hangers and are visible from the ground. Both types of gutters need inspection to make sure there are no holes and that the solder seams are still intact. Gutters are responsible for getting the water away from your home. Interior leaks in walls, in the basement, and erosion around your home can all be attributed to gutter leaks.

Maintaining your historic roof is a responsibility worth taking seriously. Generations before you managed the simple job of roof maintenance and we recognize that effort every time we look up at a magnificent, century old slate roof. Now this old roof is in your hands and it's up to you to protect it so it can stand another century against the rain and snow.

The job is easy with The Durable Slate Company. Let's protect history. Together.