Slate roofing is regarded as one of the most durable roofing systems of all time, with an expected lifespan of over 100 years. Nevertheless, slate roofs are not impervious to damage. Here are the common causes of premature slate roofing failure.
Walking on the Roof
Slate is durable, but it’s not designed to be walked on; it just doesn’t have enough flexibility to withstand the kind of pressure caused by someone standing on it. This is one of the many reasons why slate roofing installation, repairs and inspection should be left to professionals.
A knowledgeable installer would know better than to set foot on a slate roof. Cracked slate gives rainwater easy access to the roof deck, the effects of which would not be noticeable until water starts leaking into the house. A few years of freeze-thaw cycles can increase the gaps in these cracks.
Using the Wrong Type of Flashing
Flashing is the strips of metal that protect vulnerable areas, such as roof valleys, transitions between roof and wall or dormer, and the base of protrusions like vent pipes and chimneys. Asphalt shingle roofing systems typically have flashing made of galvanized steel.
Slate roofs, however, require more durable flashing: the kind that can match its long lifespan. This is why copper flashing is recommended for slate roofs: it doesn’t corrode and doesn’t require a protective coating. It also grows a natural green patina that enhances the look of the roof.
Using Poor-Quality Roofing Nails
Slate roofs also need long-lasting roofing nails. Poor-quality roofing nails will deteriorate ahead of the slate roof itself, leading to slate pieces falling off the roof. This is why slate roofing requires heavy-gauge galvanized roofing nails, which are not interchangeable with the nails used on asphalt shingle roofs. Slate roofing installation requires much handiwork as each piece has to be pierced and nailed by hand, and must be aligned properly.
Fortunately, these causes are avoidable, especially when you work with an experienced roofing contractor.
A1 Roofing & Construction is your leading provider of roof repair and installation services. Give us a call at (401) 265-1019, or fill out our contact form. We serve customers in Providence and Warwick, RI, as well as in New Bedford, MA.
