Slate doesn’t have as big a market share as, say, asphalt shingles or metal owing in part to the fact that it is one of the most expensive roofing materials out there. For the homeowners who are lucky to have a slate roof, however, this expense translates to a lasting investment. Slate is one of the very few roofing materials that age gracefully and continue to contribute to a home’s curb appeal and value decades down the road.
And we’re just getting started. Below is a list of the different benefits you can get from a slate roof.
Perk #1: Lifespan
According to the Philadelphia Historic Preservation Corporation, certain types of slate are capable of outlasting all other roofing materials on the market. Virginia and Vermont slates, for instance, easily outlive copper roofs and clay tiles, roofing materials celebrated for their century-long lifespans. And even slate types that aren’t expected to last as long easily double the lifespan of asphalt, the most popular roofing material in the country today. Examples include Penna and artificial slate, with lifespans of 60 and 40 years, respectively.
Perk #2: Weather Protection
Natural slate provides incredible water resistance, with a maximum porosity of only 0.3%. This means that even in a heavy deluge, water will just flow right off of roofing slates, preventing costly damage.
Slate can also hold its own against hail. A study conducted on S-1 rated natural roofing slate by Architectural Testing in Texas found that 3/8-inch-thick slate can withstand the impact of two-inch hail stones traveling at speeds exceeding 70 miles per hour. Even thinner (1/4 inch) slate exhibited outstanding hail resistance, surviving the impact of 1 3/4-inch ice balls traveling at 69 miles per hour.
Finally, because slate is a stiff, low-profile roofing material, it also has outstanding wind uplift resistance.
Perk #3: Environmental Impact
From an environmental standpoint, the use of slate is a good thing. It is a naturally-occurring material, which means its production doesn’t release detrimental substances to the environment. Its longevity, resistance to degradation, and the fact that it is recyclable are also big plusses because they help keep other roofing materials out of landfills. Purchasing slate from local quarries or using salvaged slate further reduces its already-low environmental impact.
Slate is also energy-efficient. It’s a great insulator and, according to the Department of Energy, can be used in cool roof installations because of its natural reflective properties.
Perk #4: Fire Protection
Slate has long been recognized for its excellent fire resistance. The 2009 edition of the International Building Code gave slate roof assemblies over noncombustible decks a Class A fire resistance rating.
Further testing by the National Roofing Contractors Association (NRCA) and the National Slate Association (NSA) showed that roofing slates installed over felt underlayment and a plywood roof deck still achieved a Class A rating. What this means is that no portions of the deck and covering were damaged during burning, nor did the underside of roof deck catch fire.
Slate roofing has plenty of advantages to offer; however, in our experience, we’ve found that proper installation still plays a critical role in maximizing these benefits. If you’re thinking about making the switch, talk to a local contractor you know you can trust. Getting a slate roof isn’t a decision to make lightly, but done right, will be something you won’t ever regret.
Carol Tedrick spearheads Tedrick Roofing’s efforts to educate homeowners and help them make informed roofing decisions. She enjoys working for a family-owned and -operated business with a strong commitment to customer care. Check out more of her posts at http://www.tedricksroofing.com/blog.