Laying fake grass on grass: A step-by-step guide

Looking to replace your natural grass with artificial turf? There are many benefits, not least no mowing, no mud and no weeds.

However, it’s absolutely vital that you prepare the ground before starting the installation process so that your new fake lawn pays you back with many years of satisfaction.

Laying fake grass directly over natural grass is definitely not the right thing to do. Firstly, there is a strong chance that weeds and surviving grass will grow through, creating an unattractive, uneven surface. A fully cleared, levelled surface with adequate drainage is the way to go if you want your synthetic lawn to go the distance. In other words, you’re going to need to remove your existing grass.

Ready to lay fake grass over a natural lawned area? Here’s all you need to know.

Materials checklist:

  • Weed membrane
  • Type 1 aggregate
  • Sharp sand for fine levelling
  • Metal or timber surround (optional)
  • Your chosen artificial grass
  • 20mm shock pad underlay
  • 40mm x 2.5mm carpet tacks
  • Artificial grass glue
  • Jointing tape (if joints are required)
  • Kiln-dried sand (for your fake grass infill – around 4-5Kg per square metre)

Tools checklist:

  • Turf cutter
  • Shovel
  • Wheelbarrow
  • Wacker plate
  • Screed bar
  • Stiff broom
  • Tape measure or straight edge
  • Sharp knife and spare blades
  • Spatula or filling knife (to spread the glue)

Before you start:

Groundwork preparation

The groundwork preparation stage is probably the most important step in laying fake grass over a natural lawn.

Always check that there are no cables or pipes delivering vital services to your property that could be potentially damaged during the groundwork process. Also be sure that your area to be turfed benefits from adequate drainage.

The first step is to use a turf cutter to remove the existing lawn. You’ll want a fully grass-free surface. Next, apply a generous dose of weed killer so you have the best chance of not seeing weeds growing through the fake grass.

Next, fit your weed membrane. This is another vital tool in your anti-weed armoury.

Now fit your edging. This is an optional step but useful if you are going to be planting the areas around your lawn. Make sure it doesn’t sit above the final grass line.

The next step is to fill the area with type 1 aggregate. Do this to around a level of 60mm. Compact the aggregate using a wacker plate, then apply a layer of sharp sand. Use a screed bar to even everything out.

Your step by step guide to installing fake grass on grass

Choose a dry day for your installation. Your base should be completely dry before you begin.

Step 1: Install your underlay

Start at one end of the space you will be turfing, making sure the underlay roll sits right up against the edge of your surround. Roll it out and then cut to the desired shape. Carry on until the entire area is covered. 

Top tip: Underlay will naturally try to roll itself back as you lay it. Placing a heavy object on each end will alleviate this issue.

Use jointing tape and fix any separate pieces of underlay together. You’ll want to create a single sheet that you can fix down around the edges of your lawned area using tacks. Place them every 10-20cm.

Step 2: Install your fake grass

Roll your fake grass out onto the area to be covered. Allow 5cm extra around all the edges so you have room to trim and create the perfect edge. Creases and wrinkles are natural, so don’t let it worry you. Leave the synthetic grass for a minimum of 2 to 3 hours, allowing it to settle so that the wrinkles disappear. Once it’s all nice and flat, you can start cutting it to size ahead of securing it down.

Top tip: Trim the synthetic grass with the underside facing upwards. Follow the stitch lines so you don’t cut through the stitches. This will provide you with a smooth edge.

If you have a large area to turf, you may need to join two or more pieces of fake grass together. Do not glue separate pieces directly onto the underlay as they will move independently when walked on, revealing all the joints. Instead, follow these jointing instructions.

How to join fake grass

Firstly, make certain that the pile of each piece of fake grass runs in the same direction.

Set the two pieces beside each other, pile upwards, and line up the edges.

Fold the edges of both pieces back on themselves about 25cm to reveal the back of the grass and the stitch lines. Cut 2-3 stitch lines down each edge. Now turn the two sections over to see how they look on the upper side ahead of sealing with the jointing tape. Apply pressure evenly along the seam so the adhesive sticks all the way along.

Now it’s time to fix the artificial grass to the underlay.

Fold the turf back and apply a layer of glue directly to the entire perimeter of the underlay. Be aware that you have limited time – around 30 minutes – to work with the glue before it goes off.

To allow the fake grass and underlay to totally bond, do not walk or place anything on the lawn for a minimum of two hours.

Step 3: Sand and brush the artificial grass

We recommend infilling the new artificial lawn with kiln dried sand. It helps fix the fake turf in place, reducing the chance of wrinkles appearing. It also protects the artificial grass fibres and keeps them looking their best. Opt for weed-free sand to keep weeds at bay.

After you have completed the infill stage, brush it through with a stiff or motorised broom. Doing this in the direction of the pile will lift the fibres.

Following fitting:

  • Brushing a fake lawn with a stiff brush or plastic rake will help keep it looking attractive.
  • Clear debris with a leaf blower, broom or leaf rake and wash away any spillages with water.
  • Take care when placing garden furniture or children’s play equipment on the fake lawn. Try to spread the load to reduce indentations.
  • Always keep barbeques and other hot objects away from any artificial lawn.