How to Lay a Patio

Planning Your Patio

Decide on size, material, and drainage direction. A patio should slope away from the house at 1:60 (approximately 17mm per metre). Mark out the area with string lines and pegs. Check for any underground services. Order materials and add 10% for cuts and waste.

Choosing Patio Materials

Concrete slabs: most affordable at £8–£20 per square metre. Porcelain tiles: premium look, very low maintenance, £20–£60 per square metre. Natural stone (sandstone, slate): premium at £25–£70 per square metre. Block paving: flexible and repairable, £15–£35 per square metre.

Step 1 — Excavate the Area

Excavate to a depth of 150–200mm (more for areas with vehicle access). Remove all topsoil and organic material. For a 4x4m patio, this creates approximately 3–4 tonnes of spoil to dispose of. Hire a skip or arrange collection.

Step 2 — Lay the Sub-Base

Compact a 100–150mm layer of MOT Type 1 (crushed stone hardcore) using a plate compactor (hire for £40–£80/day). This is the most important step — a poorly compacted sub-base causes slabs to sink and crack. Check falls constantly with a long spirit level.

Step 3 — Mortar Bed

Mix sharp sand and cement in a 5:1 ratio (5 parts sand to 1 part cement) to a stiff, crumbly consistency — not sloppy. Lay a 40–50mm bed and screed level. For porcelain tiles, use a flexible tile adhesive rather than a sand-cement bed.

Step 4 — Lay the Slabs

Place slabs firmly on the mortar bed and tap level with a rubber mallet. Check levels and falls constantly. Leave consistent joint gaps (8–15mm for natural stone, 3–5mm for porcelain). Work from a fixed reference line and don't walk on freshly laid slabs.

Step 5 — Pointing

Allow mortar bed to cure for 24–48 hours before pointing. For natural stone: mix pointing mortar (3:1 sharp sand and cement) to a firm consistency and push into joints with a pointing iron. For porcelain: use a specialist grout or resin jointing compound.