One interesting thing about composite decking is that it is easy for DIYs to install it by themselves. 

This means that if you are an intermedium DIYer and have the right tools, you can install your composite decking yourself. There are two ways to lay the composite decking on grass. 

The first way of building your composite decking is by laying it on the grass, while the other way is to raise it from the ground. 

How to lay or build your composite decking on grass will be explained in this article.

How to Build Your Composite Decking on Grass or Soil

Laying your composite on grass or soil is easy if you follow the simple steps explained below. 

tool gathered together

Step 1 Get Your Equipment Ready

Gathering the right tools will save time and money during installation.

The tools required are:

  • Pencil, Pegs
  • Measuring Tape
  • Drill
  • Spade
  • Circular Saw
  • String
  • Rubber Mallet

Step 2 Prepare the Location

Developing the location involves measuring the exact spot that your decking will cover. It can be accomplished with the assistance of a measuring tape. 

When you have gotten the length and breadth of the spot where you will place the decking, you can put pegs at the sides. 

After you have marked the sides with pegs, you can proceed to use a spade to clear grass away from it. You don’t want to build your decking directly on the ground with grass beneath it. 

After that, you should spray weed control substances on the ground so that weeds will not grow. Then, cover the location and lay the frame with gravel and a membrane

It is on this gravel that the frame that you will lay your composite deck boards on will be installed. 

prepare location
prepare location

Step 3 Posts & Frame

This part in our experience is one of the most important parts of any decking installation the frame, get this correct and you ensure maximum longevity of your project.

  • Post – Dig 500mm whole and place your 100 x 100mm post into the ground, pour concrete in the whole to fix them into position – Please see the image to the left of the frame with the post in place.
  • Joists – Once your posts have been firmly installed into place, you will then attach your joists to the posts, to build a frame, start your outer frame and then work your way in.
  • Joist Hangers – A good tip is to purchase some joist hangers when connecting your joists to the perimeter of your frame.
  • Use Noggins – Once your joists are in place, you see from the image, that a piece of wood is placed in between the joists, this is called a noggin and helps the joist and frame from rolling or losing position over time.

Step 3 Install the Boards 

Once your frame is complete then start to lay your decking boards out ready for installation and attaching to your joists.

Please note it is recommended that you use treated 4 by 2 kinds of wood for your joists, please also see the image on the right where the top of the joist has DPC tape to help with moisture absorption on the frame. 

Joists should be spaced no greater than 300mm when installing boards to the frame.

You will start using bullnose boards with the outer board first, if not please start from the fixed object ensuring a 25mm gap is left between the board and the fixed object.

After securing the outer boards, you can start attaching more boards on the inside of the frame. 

Step 4 Arrange the Decking

Arranging your composite decking on the joists is the next thing to do after building the frame. 

This can be perpetrated effortlessly, and you should embark on the task from the side of a house or a wall. 

If the decking is not joined to the house, you should start from one end and take it to the next.

Note that there should be at least a 6mm space end to end between the deck boards. This is to accommodate the expansion of the composite decks when there is a temperature change.

Step 5 Finish the Decking

Finishing the decking means that you should cover the edges with trim if you wish to do so.


Installing your composite decking on grass is easy and can be completed without the need to hire a professional. Following the simple steps above will guide you on how to lay decking onto the grass. If you are unsure about the installation process then consulting a professional is advised.