Granite wall cladding

Why granite makes good wall cladding

Granite is hard, dense and does not burn. It protects the wall behind it. It keeps its look in sun, rain and dirty air. Inside, its deep colour and shine make a strong feature wall, lobby or fireplace surround.

Outside, façade granite gives a building a solid, confident face that people notice.

• Weather and fire: stone does not burn, and sun and rain do not wear it down.
• Look: polished, honed, flamed, brushed and rough-split finishes look very different on the same stone.
• Easy care: no painting and little upkeep.
• Choice: panels, tiles and cut-to-size pieces for walls, columns and outside walls.

Finishes, thickness and weight

Inside walls can use thinner panels. Outside walls need thicker stone and fixings designed by an engineer. Granite is heavy: about 55 kg per square metre at 20 mm. The wall must be able to carry it.

• Inside: panels about 10–20 mm thick, depending on their size and the fixing.
• Outside: often 20–30 mm, with fixings designed for the stone and the building.
• Finish: polished looks rich inside. Flamed, brushed or rough-split suit outside walls and weather.
• Weight: plan for the load on the wall, the brackets and any frame behind.

Fixing and details

How the stone is fixed matters most. Small tiles inside can be stuck with the right adhesive. Big panels, high walls and all outside walls must be fixed with metal fixings. Use stainless steel anchors or a ventilated wall system.

• Fixing: stainless steel brackets and anchors, planned by an engineer, for outside walls and heights. Adhesive alone is not enough.
• Movement gaps: leave small gaps at corners and at set spaces, because stone grows and shrinks a little with heat.
• Joints and sealants: use sealants and adhesives made for natural stone, so they do not stain it.
• Corners: mitred (cut at an angle) or lipped corners give a clean, strong edge. Plan them in the drawings.

Sealing and care

Inside stone needs only a damp cloth and a mild cleaner. Outside stone can be washed now and then with water and a soft brush.

• Sealing: a good idea in wet places, like bathrooms, and around fireplaces.
• Do not use: acid cleaners, scrubbing pads or a strong water jet close to the joints.
• Check: look at outside fixings and joints now and then, as part of building upkeep.

Mistakes to avoid

• Using only adhesive for heavy panels, outside walls or heights.
• Forgetting the weight when you choose the wall or the frame.
• Using ordinary steel fixings. They rust and stain the stone.
• Leaving out movement gaps.
• Using adhesives or sealants that stain light stone.
• Mixing panels from different lots, so the colour changes across the wall.