Changes

<p>An alternative drainage layer solution is to use a granular medium to increase the tortuosity of the flow path and slow peak flow rates. </p>

<p>An alternative drainage layer solution is to use a granular medium to increase the tortuosity of the flow path and slow peak flow rates. </p>

<h4>Geotextile</h4>

<h4>Filter Layer</h4>

<p>The geotextile layer is included to prevent migration of the planting medium into the drainage layer.  Current advice is to specify a free draining textile to prevent potential water-logging of the planting medium. Observations green roof assemblies have shown a reduction of flow from specifications owing to interactions of medium particles with the textile.</p>

<p>The geotextile layer is included to prevent migration of the planting medium into the drainage layer.  Current advice is to specify a free draining textile to prevent potential water-logging of the planting medium. Observations green roof assemblies have shown a reduction of flow from specifications owing to interactions of medium particles with the textile.</p>