flagstones

Flagstones are broad, flat slabs of natural stone used for paving and flooring. They are typically rectangular or irregular in shape, with thickness generally in the range of 1 to 2 inches (2.5–5 cm) for outdoor use and slightly thinner for interior applications. The term encompasses a variety of rock types, cut to expose a flat face suitable for walking surfaces.

Common flagstone materials include slate, sandstone, limestone, quartzite, and other sedimentary or metamorphic rocks. Colors vary by stone—from gray and buff to red, tan, or green—depending on mineral content and quarry source. Flagstones are quarried in blocks and cut or cleft into slabs.

Flagstones may be finished by cleaving (natural split surfaces) or by sawing to a smooth face. A cleft surface often provides a rougher, slip-resistant texture and a more rustic look, while sawn faces yield a flatter, uniform surface. Edges may be chamfered or left natural.

Common uses include outdoor patios, walkways, and pool decks, as well as rustic indoor floors or entryways. Installation may be mortared to a concrete or compacted-subbase, or dry-laid on compacted gravel. Joints are filled with sand, mortar, or polymeric material, and thicker stones often require precise base preparation to prevent movement.

Maintenance is relatively simple but varies by stone type. Periodic sealing may be advised for some stones; routine cleaning and prompt replacement of cracked pieces help maintain functionality. Proper drainage and regular inspection of joints reduce frost damage and shifting.