A renaissance of slate roofing

With all of the inroads that natural stone is making in design - for applications such as kitchen countertops, flooring, walls and exteriors - it is interesting to note that one of the most traditional applications of natural stone in North America, roofing slate, is also enjoying success in the 21st century.

Slate roofing was one of the first architectural applications of natural stone in this country, and its use symbolizes tradition and history in building. Today, slate roofing is being sold for a broad range of new construction projects as well as historic preservation work. These projects include residences as well as historic churches and other building types.

In this issue of Stone World, we take a look at the installation of slate roofing for two very different project types. The first is a traditional church located near the Atlantic Ocean in New Jersey ("Rebuilding with Riverstone slate," page 78). Over the decades, the harsh Northeastern climate, coupled with the salt-laden high winds coming off the ocean - caused the roof to deteriorate. And when it came time for a replacement, the church's administration selected natural stone over the man-made replacement materials that permeate the market. "There was a selection process where various materials were considered to replace the existing Pennsylvania slate," explained Dianne Waters, the business administrator for the church. "But, on a cost-per-year basis over the life span of the material, Riverstone natural roofing slate, which was provided by Williams & Sons Slate & Tile, Inc. of Wind Gap, PA, turned out to be less expensive than asphalt shingle, ceramic tile or any of the new imitation slate products." The slate chosen for the project has an expected life-span of approximately 100 years.

The long-term benefits of natural slate were also a determining factor for a private residence in Vermont, which is also featured in this issue ("Slate portrays New England-style architecture," page 84). The owner and designer of the residence, Alan Pratt, pointed out that using natural slate offered significant longevity over cedar, which is also commonly used for residential projects. "We didn't choose cedar because it doesn't last very long," he said. "It is a new growth timber that only has a 20-year life expectancy." Pratt pointed out that the 100-year life expectancy of the slate actually made it more attractive in price than other materials. "Most people think installing a slate roof is not cost effective, when in fact, if you compare slate and its life span to other materials, it's a cost-effective material," he said.

And while there are many generations-old suppliers of slate roofing still in existence, the popularity of the product has also given rise to new fabricators in the industry. The supplier of the residential project, Vermont Specialty Slate of Brandon, VT, began in 1995 as a supplier of slate signage and similar products. Now, only seven years later, it produces roofing slate for distribution nationally as well as in Canada, and it supplies a full range of architectural products. ("Carving a niche in the slate industry," page 32).

So it appears that the continued popularity of roofing slate not only enhances the architectural landscape, but it also has allowed for expansion of the industry as a whole.