How to lay foundation for paving slabs

Before paving, you'll need a good foundation. Here's how you lay one.

Level of difficulty

Level 2: Intermediate

What you need

  • String lines
  • Pegs
  • Bricks
  • Spade
  • Sledgehammer
  • Garden roller
  • Builder’s sand
  • Bricklaying trowel
  • Garden rake
     

The steps to follow

  1. Wrap a string line around two bricks or pegs and stretch it across the area where you plan to build the foundation.
  2. Use a spade to remove the turfs and the topsoil where you plan to build the foundation.
  3. Dig down to a depth of about 20 cm (8 in). You'll need this depth to fill in about 10 cm (4 in) of hardcore, 5 cm (2 in) layer of sand, and the layer of concrete or paving material.
  4. With a sledgehammer or a garden roller, compact the base of the trench.
  5. Next, add a layer of hardcore to the base, which should be 10 cm (4 in) deep.
  6. Compact it with a sledgehammer or a garden roller.
  7. Spread a layer of builder's sand of about 5 cm (2 in) deep.
  8. Smooth the surface with a garden rake.
  9. Next, add the concrete on top of the builder's sand.
  10. Tamp down and flatten the layer of concrete with a piece of timber. The piece of timber should be long enough to span the area.
  11. Let the foundation set and dry before starting your next project.
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