Paving Stones

Slate is one of the prime building materials, and is widely used in roofing, wall coverings and floors – and increasingly, in outdoor patio and courtyards. One of the hardest of the stones used for paving purposes, slate offers versatility, durability and a stunning variety of colors and patterns to suit almost any setting. Among the advantages offered by slate tiling for a patio floor or back yard walkway are affordability and utility – even when wet, most slate is not slippery.

Slate is available in a wide range of colors, from black to green to rose. The stones may be of one mostly smooth color, or a variegated combination of more than one. Particularly stunning are black slate with rose and violet patterning that resemble flower bursts in the natural stone.

Color isn’t the only variation available in slate. There’s a wide variety of surface textures available, thanks to modern techniques that can be used to affect the appearance and surface of the slate stones. Slate may be hammered, honed, polished, sand-blasted, sawed or flamed. Among the available textures are:

• split face – the roughest cut, the bare face of the slate after it has been split
• Saw-cut – a rough surface that shows the marks of the saw
• Sand-blasted – the stone is dampened then fired with an acetylene torch. The result is fissures and color changes to the stone.
• honed – the surface is sanded smooth, but not polished. Honed surfaces show wear more than rough surfaces, but not so much as polished ones.
• Polished – brought to a mirror like sheen by abrasives and sanding. Polished stone isn’t recommended for patio surfaces where regular use puts a great deal of wear and tear on the finish.

Slate is relatively soft compared to other stones, and cuts easily with a circular saw, making it an ideal stone to work with for patios and stone edgings. Because of this ease, it’s possible to use slate paving stones for intricately pieced patterns like circles and starbursts, though it makes a beautiful and simple floor when laid in a plain square pattern, or a crazy pattern.

Slate is suitable for a do-it-yourself project if one can manage heavy lifting and cutting. The work is meticulous, and requires the construction of a form to hold a bed of sand into which the slates will be set. Slate can also be set into a concrete base, but most experts recommend that concrete setting be left to the experts as it requires quick working and fitting to set the stones in place before the concrete dries.

Slate is quarried in the UK, but may also be imported from China or India. Indian slate in particular comes in a wide choice of colors. Experts warn, though, to watch the quality of slate carefully. Slate used for patio floors, walkways and steps should be at least 2 inches thick, and have a chamfered edge that slopes inward from the top down to help set the stone properly and keep the setting material from washing out in the rain.