Artificial grass and drainage explained

How the water gets away

Water passes through perforations in the grass backing, through the laying course, into the sub-base, and then into the subsoil or a drainage feature. If any of those layers is blocked or too tight, water backs up and sits on the surface.

This is why the most common cause of a puddling artificial lawn is not the grass at all — it is a compacted, fine-graded base with nowhere to release the water.

Hertfordshire ground conditions

Much of the county sits on clay-influenced soils that drain slowly, with chalk in places and, on newer estates, thin topsoil over heavily compacted subsoil left by construction traffic. Any of these can hold water for days after heavy rain.

During a survey we look at where the garden falls, whether water marks show along the house or the fence line, and how the existing lawn behaves after rain.

Drainage solutions we use

• A deeper open-graded sub-base to increase the volume the base can hold
• Falls set away from the property across the whole area
• Channel drains where the lawn meets a patio or the house
• Soakaway pits filled with clean stone, sited away from foundations
• Perforated land drains in gardens with a persistent problem

What good looks like

After heavy rain a well-built artificial lawn should be walkable within minutes, with no standing water and no soft, spongy patches. If your existing lawn does not behave that way, the base is the place to investigate.