8,254
edits
Changes
Jump to navigation
Jump to search
Line 32:
Line 32: <h4>Loading</h4>
→Planning Considerations
===Planning Considerations===
===Planning Considerations===
<div class="col-md-8">
<div class="col-md-8">
<p>Green roofs offer a variety of co-benefits beyond stormwater management. In urban centres 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 in 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 stormwater capture benefit is restricted to the areas with vegetation planted. Another increasingly popular use for rooftop space is in urban farming. Again the 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. 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>
<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 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>Rooftop farming is also becoming common in some Ontario cities. Again consideration should be given to the proportion of the roof actually planted. Where large open expanses of roof are being cropped, measures may be required to reduce erosion of exposed planting medium. Any digging or furrows will reduce the stormwater benefit.
<h4>Biodiversity</h4>
<h4>Biodiversity</h4>
Biodiversity opportunities are optimized by planting a variety of species. General advice on this has been prepared by the City of Toronto[https://www1.toronto.ca/City%20Of%20Toronto/City%20Planning/Zoning%20&%20Environment/Files/pdf/B/biodiversegreenroofs_2013.pdf]. In the long term, the richness of species increases owing to 'volunteer species'. The desirability of this diversity varies with the aesthetic concerns of the green roof owner. Lighter maintenance has been shown to result in
</div>
</div>