Changes

<h4>Filter Layer</h4>

<h4>Filter Layer</h4>

The [[Geotextiles| 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.

The [[Geotextiles| 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.

<h3>Planting Medium</h3>

<h3>Planting Medium</h3>

{{:Green_roof_media}}

{{:Green_roof_media}}

<h3>Irrigation</h3>

<h3>Irrigation</h3>

Regular irrigation has been shown to substantially reduce the stormwater capture benefit of an extensive green roof<ref>[http://ascelibrary.org/doi/abs/10.1061/(ASCE)HE.1943-5584.0001534]</ref>.   

Regular irrigation has been shown to substantially reduce the stormwater capture benefit of an extensive green roof<ref name=Hill/>.   

One way to reduce the irrigation used on green roofs is through the use of smart technologies. Responsive sensors that suppress irrigation after a rainstorm are routinely attached to green roofs to conserve water. Improvements can be made by instead using a 'soil' moisture sensor to trigger irrigation. State-of-the-art management systems now use predicted weather data to suppress irrigation ahead of storm events, see [[digital technologies]].   

One way to reduce the irrigation used on green roofs is through the use of smart technologies. Responsive sensors that suppress irrigation after a rainstorm are routinely attached to green roofs to conserve water. Improvements can be made by instead using a 'soil' moisture sensor to trigger irrigation. State-of-the-art management systems now use predicted weather data to suppress irrigation ahead of storm events, see [[digital technologies]].   

Due to their limited water retention capacity, many green roofs are coupled with a rainwater harvesting cistern, to capture the excess water. It then becomes desirable to use as much harvested water to regain the cistern capacity,  Green roofs can be irrigated to saturation daily throughout the growing season without damaging the vegetation.  

Due to their limited water retention capacity, many green roofs are coupled with a rainwater harvesting cistern, to capture the excess water. It then becomes desirable to use as much harvested water to regain the cistern capacity,  Green roofs can be irrigated to saturation daily throughout the growing season without damaging the vegetation.