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Paving Installation Guide

Sub-Base Requirements

A solid, well-draining sub-base is the foundation of any long-lasting paved area. Pedestrian patio: 75-100mm compacted Type 1 hardcore (crushed concrete or MOT stone). Driveway: 100-150mm compacted Type 1 hardcore. Without adequate sub-base, slabs will rock, crack, and sink within a few years. The sub-base must be compacted with a plate compactor (hire from a tool hire shop, approximately £60/day) — using a hand rammer is insufficient for larger areas. For clay or soft soils: increase the depth

Laying Methods

Dry mortar method (patio): lay slabs on 5 spots of firm mortar (one in each corner and one in centre), tap level with a rubber mallet, grout with dry sand or kiln-dried sand pressed into joints. Wet bed method (professional): spread a full mortar bed (4:1 sharp sand:cement, semi-dry), set slabs in one operation. This is better for large format slabs and driveway use. For driveways: use a full wet bed, and ensure the mortar strength is appropriate for vehicle loading. Indian sandstone and natural

Drainage Requirements

From November 2008, replacing or extending front garden paving with impermeable materials requires planning permission in England unless a drainage system is incorporated. The permitted development right requires either using permeable paving (block paving with open joints, gravel, resin-bound) or directing water runoff onto a lawn or planted area. For rear gardens, there is no equivalent restriction. Newly paved areas should have a minimum fall of 1:80 (approximately 12mm per metre) away from t

Jointing and Sealing

Joint width: typically 10-15mm for standard paving, 3-5mm for precision-cut porcelain. Narrow joints require more accurate cutting. Jointing materials: kiln-dried sand (brush in, compact, repeat until full — budget option). Polymeric sand (activates with water to form a semi-rigid joint — resists weeds and ants effectively, £15-25 per 15kg bag). Mortar pointing (durable but cracks if sub-base settles — can look untidy if not done carefully). Sealing: porcelain requires no sealing. Sandstone bene