What to put under artificial grass for drainage?

All artificial lawns should be installed with artificial grass drainage system underneath to ensure the longevity, cleanliness and appearance of the lawn.

Our artificial turf installations are often chosen as an alternative for a lawn with poor drainage. Poor drainage may occur in a lawn that does not face the sun, has a high clay content, or as commonly found in a new build property made up of rubble and earth. We install our lawns with a sub-base to keep the lawn stable and to allow for the drainage of water into the ground below, however you may need more extensive drainage intervention in addition to our standard method if your drainage is particularly poor.

After the existing lawn is removed to a depth of between 55 and 70mm, a sub-base consisting of type 1 limestone then a layer of grano dust is distributed. Even though these layers should be flattened with a wacker plate, limestone and grano dust are both porous types of aggregate which allow water to drain from the surface into the ground below. This sub-base should cover the entire area that earth has been removed and distributed at an even and consistent level.

How does the grass drain water? The roll of grass is manufactured with a holed backing that is concealed within the pile height and not visible when laid. Water simply drains straight through these holes and into the aggregate base below. As you might expect, after heavier rainfall the grass may take longer to drain and dry than with a light shower.

If you intend to lay your grass on top of a surface such as decking, tarmac or paving which has poor drainage then artificial grass will not improve the drainage as there is no change to the existing base. As a general rule if the drainage was poor before we would not recommend you add artificial grass on top of the surface.

Interested in getting a quote from the experts? Request an installation quote.