Techniques for Laying Flagstone

Dry-Lay Your Pieces

• Dry-lay your pieces. In other words, place them on the ground and work out an attractive arrangement that works with the shapes of the pieces you have. Aim to leave gaps between the stones of between 1/2 inch to 1 1/2 inches. Trim your stones, if necessary, with a brick bolster and hammer, to make them fit within your overall scheme. Do not use all your large pieces together as your design will look unbalanced.

Prepare Your Foundations

• Excavate your site to a depth of 6 inches. Allow 4 inches at each side for the edging and stakes. Pour in gravel to a depth of 2 inches. Tamp it down with the end of a rake or a length of timber to compact it. Install 2 inch wide, pressure-treated wooden edging around the perimeter, staking it with off-cuts. Fix your edging onto your stakes using galvanized nails, as they are weather resistant.

Lay Your Pieces

• Lay the flagstones on your gravel foundations, following the design you worked out earlier. Tap the stones with a rubber mallet to set them in place. Aim to have a surface that is roughly level, though not entirely so. Walk on your flagstone area when you have laid all your stones, to test it. Lift any stones that are not sitting properly and either add more gravel below them, or scoop some out with a trowel.

Fill the Gaps

• Pour sand over the edges of your flagstones and brush it into the gaps. Pack the sand down further between the stones with a small piece of wood. Aim to have the gaps flush, or level, with the surface of the stones. Spray the flagstones lightly with water, using a hosepipe or watering can, to settle the sand. Add more sand, as required, to fill any crevices that open up.