Slate is one of the few building materials that actually becomes tougher and more resilient with age, and slate roofs dating back to the 18th century still protect buildings today.
The color and quality of slate varies with its geographic origin, but all slate is naturally impervious to the elements. Slate graded the highest for strength and hardiness is practically non-porous and makes the most lasting roofing material known. The best slate is quarried in the northeast corner of North America, with the absolute finest coming from Vermont, New York and Canada.
The installation of a quality slate roof varies greatly from the installation of an ordinary shingle roof-from the skills to the tools, right down to the nails that hold the slate on place. Defects in slate roofing so often blamed on the material are invariably the result of poor or inexperienced workmanship. An exprecianced slate will deftly employ the ripper, stake, hammer, and punch to create or recreate a roof slate by slate. Some projects require only the replacement of a certain percentage of the old or damaged slates. Other roofing projects require that the slates be removed, the flashing details and underlayment replaced, and the original slates re-laid. Flashing and detail work in copper, iron, tin or other metal finishes the job.
You’ll find slate roofs on buildings across America and throughout Europe. Buildings as diverse as the Lincoln Memorial in Washington D.C. and the Saxon Chapel. At Stratford-on-Avon in Wiltshire, England wear hand-laid rooks of slate.
It takes the eye of an experienced slate craftsman to properly install, maintain and repair a slate roofing system.