Slate Roofing - Suppliers, Vendors, Sources, Manufacturers

Slate roofing is one of the most distinguished building products . It graces many of the most impressive buildings in the world. Cathedrals, palaces, residential homes, and castles have incorporated this long lasting building material as a weathershield. In fact, it was the king of roofing materials at the turn of the twentieth century. United States slate consumption was at its highest in 1902.

Slate roofing is really nothing more than mud. Mud that has been squeezed and heated. Fine particles of clay and silt build up in thin layers at the bottom of shallow seas or at the mouths of large river deltas. These sediments then turn into a rock called shale. Mountain building processes can heat and pressurize the shale changing its chemistry. The clay and silt crystallize into quartz, chlorite, and different micas, all of which are very durable materials. This is one of the reasons why slate lasts so long. The chemistry change also imparts a negative quality. The metamorphosis that creates slate makes it brittle. This characteristic is responsible for many of the common slate roof failures.

Slate roofing doesn't absorb much water at all. However, the water it does absorb can and does destroy it over time. Rain water in industrial areas can turn into mild acid. This acid attacks the minerals in the slate and can dissolve them. Water which turns to ice causes tiny micro fractures which blow the slate apart. Freezing and thawing cycles are like mini jack hammers that take layer after layer of slate off a shingle. Slate that dries rapidly between periods of precipitation minimizes this damage. Spaced sheathing or battens allows air to circulate under the slate. This simple technique can add years to your slate roof if you are thinking of building a new home.

If you are considering a new house or building and choose to use slate roofing, you now have a new option. There is a system by which the slate hangs from tracks. There are no nails in the slate that can pinch them. Furthermore the tracks hold the slate off the roof deck allowing adequate ventilation. It is an excellent way to attach slate to our modern plywood sheathed roofs.