French Drain & Trench Installations


Using Geotex Membrane in French Drain Systems

Good drainage is required to ensure groundwater doesn’t build up, as it can cause damp and rotting to building foundations, basements and homes. One of the most reliable methods for preventing this is installation of a French Drain, a technique that has been improved and utilised for many, many years. The old fashioned way of doing this was to fit the perforated drain pipe without protection or backfill, but this results in clogging of the drainage slots/holes, extra maintenance and potential re-build of the entire system. In more recent times, contractors have have improved this key solution, incorporating gravel and non-woven geotextile membrane.

As seen below, a small bedding of gravel is used underneath the pipe and then as a backfill on top. This is then wrapped in non-woven geotex. Using a geotex fleece such as 80gsm NW6 or 100gsm NW8 prevents the need for regular maintenance by only allowing water to pass through, thereby stopping other debris and mud from entering the pipe and blocking the flow of water. The geotextile membrane also offers protection from debris that could potentially damage the perforated drainage pipe.


French Drain Diagram