Hardscape Patio Construction Guide
A solid interlocking paver patio relies on three layers: a compacted gravel sub-base, a level sand bedding layer, and paving stones.
Our professional paver calculator estimates the stone count, required gravel sub-base volume, and bedding sand quantities needed to construct stable, level patios.
Calculating Quantities
To calculate the required number of paving stones, divide the total patio area by the surface area of a single paver. We add a waste margin (typically 10%) to account for perimeter cuts and joints.
1. Total Patio Area: 20.0 m².
2. Paver Dimensions: Length = 200 mm (0.2m), Width = 100 mm (0.1m).
3. Single Paver Area: 0.2m × 0.1m = 0.02 m².
4. Gravel Sub-Base Depth: 100 mm (0.1m) | Bedding Sand Depth: 25 mm (0.025m).
5. Net Paver Pieces: 20.0 m² ÷ 0.02 m² = 1,000 pavers (1,100 pieces with 10% waste).
6. Gravel Sub-Base Volume: 20.0 m² × 0.1m = 2.0 m³.
7. Bedding Sand Volume: 20.0 m² × 0.025m = 0.5 m³.
The Importance of a Compacted Base
A patio is only as stable as its foundation. Standard hardscape specifications require 4 inches (100mm) of compacted crushed gravel for pedestrian patios, and 6 to 8 inches (150-200mm) for driveways. The sub-grade and gravel base must be compacted using a plate vibrator to prevent settling and surface waviness over time.
Frequently asked questions
What gravel is best for paver bases?
Crushed run gravel (3/4-inch minus) is standard because it packs densely to prevent settlement.
How thick should the sand layer be under pavers?
The bedding sand layer should be exactly 1 inch (25mm) thick. A thicker layer can cause the pavers to shift under load, while a thinner layer makes leveling difficult.
How much sand is needed for paver joints?
For standard joints, plan for about 1 bag (50 lbs) of joint sand or polymeric sand per 75 to 100 square feet of patio area.