Can artificial grass be installed over timber decking

Can Artificial Grass Be Fitted Over Timber Decking?

Artificial grass is a popular way to transform a garden space quickly, but many people ask whether it can be installed directly over timber decking. The short answer is yes, it can—but only if the right steps are taken to protect both the decking and the artificial grass.

The Challenges of Decking as a Base

Timber decking is not a solid, permanent surface like concrete or slabs. Over time, it can:

Warp or shift as it weathers.

Leave uneven gaps that can show through the grass.

Hold moisture, which increases the risk of timber rot.

If decking is already soft or damaged, fitting artificial grass on top will only hide the problem temporarily while the structure beneath continues to deteriorate.

Preventing Rot

One of the main concerns is rot caused by trapped moisture. Artificial grass, once laid, reduces air circulation and sunlight reaching the timber. Without proper preparation, this creates the perfect environment for dampness.

Here’s how to reduce the risk:

1. Check the condition of the decking first – Any rotting or unstable boards should be replaced or reinforced.

2. Apply an oil or spirit based protective treatment – Use a quality wood preservative or rot-protection coating before installing grass.

3. Ensure drainage and ventilation – Adding a drainage underlay or aquapad helps water run off instead of sitting directly on the decking.

4. Use PU backing artificial grass NOT latex backed, because latex is much more absorbent, so drying is hindered.

When Is It a Good Idea?

Installing artificial grass over decking works best when:

The decking is in good condition.

You want a quick makeover without the expense a full landscaping project.

You’re happy with a slightly softer surface underfoot compared to grass laid on a firm sub-base.

When Not to Do It

Avoid laying grass over timber if:

The decking is old, unstable, or already showing signs of rot.

You want a long-term solution with maximum durability. In these cases, removing the decking and preparing a proper sub-base is the smarter investment.

Final Thoughts

Artificial grass can successfully be laid over timber decking, but it's not advised. It can look great if done correctly. However, the biggest risk is hidden rot, so preparation is everything. By treating the timber, adding drainage, and ensuring a stable surface, you can extend the life of both the decking and the grass to an extent. Timber decking will not last as long if artificial grass is fitted over it.