Planning & preparation
- Paving slabs come in a wide range of colours and sizes and can be laid in a variety of patterns. There is something to suit every budget so be sure to take a look at the range and plan a design you are going to enjoy for years to come.
- Once you know the dimensions of the slab you’ve chosen to use, make a detailed plan so you can minimise the need to cut tiles.
- Having planned your patio, it’s a good idea to lay the slabs out into position so you can do one final check of measurements, and ensure you are laying a pattern you’re happy with. Make a note or take a photograph of your preferred layout.
- If your patio is directly next to your house, then you’ll need to lay it so that it is 150mm below the damp proof course.
- To encourage rainwater run-off, your patio should have a fall that runs away from the house or outbuildings. A 1:60 (16mm per metre) fall is generally recommended.
- If your patio will adjoin your lawn, for ease of mowing, it should sit 10mm below ground level.
- It’s a good idea to have some help when lifting slabs, for both safety and speed of completion.
Do it right
- If you are using slabs that come from different pallets, it’s a good idea to mix them up; this will help to disguise any slight variation in colour.
- If you are removing turf, it’s best to save some in case you want to fill in any gaps between your lawn and the new patio.
- Wait for dry weather before applying kiln dried sand.
- Wear suitable footwear and gloves when handling slabs, sand, gravel or cement, and when digging.
- If using a wacker plate, you should wear ear defenders and steel toe-capped boots.
- When using a mortar mix, or Slablayer, wear a dust mask, safety goggles and protective gloves and be sure to follow manufacturer’s instructions.
- Wet and dry cement can cause irritation and burns, so handle carefully, covering skin and immediately washing off any cement that accidentally makes contact.
- Always wear protective gloves, safety goggles, and a dust mask when mixing concrete.
- If you’re using heavy paving slabs or lifting any other heavy items, ask someone to help.
- Patios are hard wearing and easy to maintain but regular brushing and washing will stop the buildup of algae and will keep your patio looking in top condition.
- The joints are key to your patio’s stability, so look after them by filling in any gaps that appear over time and removing any breakthrough weeds.
Step by Step
Before starting to lay a patio, you should use a CAT tool to make sure there are no hidden cables or pipes where you intend to excavate.
Using pegs, string, or a builders line, mark out the position of the patio.
Check each corner is perfectly square with a set square, adjusting as necessary.
Mark the edge of the patio with a spade or lawn edger, all the way around, before removing the pegs and string.
When you dig out, you’ll need to allow for 100mm of MOT Type 1 or hardcore, 25mm of Slablayer, plus the thickness of your chosen paving slab. Don’t forget to include the necessary fall in your calculations, and to maintain it throughout the build.
Add half of the MOT Type 1 or hardcore, to create a 50mm layer, and rake it so it’s roughly level.
Compact the area with either a tamper or a wacker plate to form a very stable base. Add the remaining MOT Type 1 or hardcore, to create an overall depth of 100mm and, once again, compact.
Now add the Slablayer, raking it out to a depth of 25mm.
Following the manufacturer’s instructions, use a watering can with a fine rose, or a spray gun, to apply water, then rake again to level the surface.
Starting in the corner at the highest point of the patio, dampen the underside of the first slab and lay it.
Gently tamp down on the surface of the slab with a rubber mallet to bed it in. The first slab is used as the guide for all the others to follow, so make sure it’s absolutely level and square.
Continue to lay slabs, not forgetting to leave space for your required joint width.
Use offcuts of wood as spacers to maintain a consistent gap between slabs.
Regularly check the levels, including the fall you’ve allowed, as you go along.
Slablayer needs to dry slowly over a few days, so cover the patio with plastic sheeting if rain is forecast.
Fill in the joints with either Slablayer or dry mortar mix (4 parts sand to 1 part cement). Mix with enough water to create a damp, but not wet consistency and apply to the joints with a trowel.
Brush any excess Slablayer or mortar from the face of the paving slabs, before it can set and stain the surface.