A solid, level base is essential for any long-lasting patio. One of the key materials in creating this base is sharp sand, but it must be combined with cement to provide the strength needed to keep your paving slabs stable. In this guide, we’ll take you through the steps to prepare your patio base using sharp sand and cement, ensuring a durable and professional finish.

Why Use Sharp Sand?

Sharp sand, also called grit sand or coarse sand and part of our Quarried Sand & Ballast range, has a gritty texture and larger grains compared to building sand. This makes it ideal for mixing with cement for laying patios, as it provides good drainage and stability. However, slabs should not be laid on quarried aggregates such as sharp sand alone, as this can lead to movement over time. A wet mix of sharp sand and cement gives a firm and reliable base. 
  
Step 1: Plan and Mark Out Your Patio Area

Begin by measuring and marking out your patio area using string lines or wooden pegs. Decide on the size, layout, and whether a slight slope is needed for drainage (known as a fall). Remove any turf or topsoil from the area to a depth of about 150–200mm, depending on the thickness of your slabs. 
  
Step 2: Install the Sub-Base

Before adding the sand and cement mix, you’ll need a sub-base. Use MOT Type 1 or similar crushed stone. Spread it evenly to a depth of around 100mm, then compact it thoroughly using a vibrating plate compactor. This layer provides strength and helps prevent the patio from shifting. 
  
Step 3: Prepare and Lay the Wet Mix

Once the sub-base aggregates are in place, you can prepare your bedding layer. Mix sharp sand and cement at a ratio of around 5:1 (five parts sharp sand to one part cement) with enough water to create a damp, workable consistency — not too wet, but just moist enough to bind. 
  
Spread this mix to a thickness of about 30–50mm across small areas as you work. Lay each slab onto the wet mix, tapping it down gently with a rubber mallet and checking with a spirit level to ensure it is even and aligned with surrounding slabs. The wet mix helps hold the slabs in place and prevents movement. 
  
Step 4: Jointing and Finishing

Once all slabs are laid and level, brush kiln-dried sand or apply a jointing compound into the gaps between slabs. Lightly water the area if using kiln-dried sand so it settles into the joints. Allow the patio to set and cure properly before using.