Changes

===Planning Considerations===

===Planning Considerations===

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<p>Green roofs offer a variety of co-benefits beyond stormwater management. In urban centers they are often constructed to accommodate a roof terrace or amenity space. In this scenario the stormwater capture benefit is restricted to the areas with vegetation planted.  Another increasingly popular use for rooftop space is for urban farming. Again, the stormwater capture benefit is restricted to the areas with planters.</p>

<p>Green roofs offer a variety of co-benefits beyond stormwater management. In urban centers they are often constructed to accommodate a roof terrace or amenity space. In this scenario the direct stormwater capture benefit is restricted to the areas with vegetation planted.  Another increasingly popular use for rooftop space is for urban farming. Again, the direct stormwater capture benefit is restricted to the areas with planters.</p>

<p> To maximize the utility of a green roof as a low impact development tool, coverage with planting should be maximized. In many cases this means only inaccessible spaces are used. Within the scope of green roof coverage, there is a further distinction made between 'intensive' systems over 15 cm deep, and the more commonly employed 'extensive' systems, which are 10-15 cm deep. Specialized, shallow systems exist but their application is limited. </p>  

<p> To maximize the utility of a green roof as a low impact development tool, coverage with planting should be maximized. In many cases this means only inaccessible spaces are used. </p>  

<h4>Amenity</h4>

<h4>Amenity</h4>

<p>Roof gardens with a high proportion of impermeable surface are popular in high rise developments. These amenity terraces are often described as green roofs, but the LID benefit applies only to the vegetated areas. The stormwater benefit of all kinds of green roofs is maximized by combined with [[Rainwater Harvesting|rainwater harvesting]] for subsequent irrigation. Sedum and native species have all been shown to thrive with daily irrigation to saturation[http://grit.daniels.utoronto.ca/green_roof_image_index/#]. </p>   

<p>Roof gardens with a high proportion of impermeable surface are popular in high rise developments. These amenity terraces are often described as green roofs, but the LID benefit applies only to the vegetated areas. The stormwater benefit of all kinds of green roofs is maximized by combined with [[Rainwater Harvesting|rainwater harvesting]] for subsequent irrigation. Sedum and native species have all been shown to thrive with daily irrigation to saturation[http://grit.daniels.utoronto.ca/green_roof_image_index/#]. </p>