Reforesting Cities

A great post on Urban Omnibus investigates the potential of implementation of urban reforestation blended into existing buildings in our urban areas. From author Vanessa Keith, author of the article: "Retrofitting our urban building stock to address climate change need not be limited exclusively to increasing their energy efficiency. If “one of the primary causes of global environmental change is tropical deforestation” (Geist & Lambin, 143), then we should approach the adaptation of our buildings as an exercise in reforestation."


:: image via Urban Omnibus

While the ideas of terrestrial re-forestation have been discussed often in urban areas, the proposals attempt to incorporated this into existing building stock is a unique way of augmenting this. The post goes through a range of typologies of interventions including white roofs, greenscreens, green roofs, windbelts, and a range of blue-roof strategies (see Veg.itecture for more exploration of this).


:: image via Urban Omnibus

So, pulling it all together, starts to looks like a eco-district scale project typology, with a range of building and terrestrial opportunities exploited: "Large scale urban farming which takes place indoors and on large expanses of roof, greenscreens to let plants to climb the vertical surfaces of the city, trees which are now able to grow on the city roofscape. Roof ponds and artificial waterfalls for cooling and electrical generation. Solar and wind devices which form sculptural elements in the city, performing a function as well as having an aesthetic. Ports for plug-in electric vehicles which gather energy from photovoltaics. Solar panels incorporated into street poles, and vertical wind turbines which form a rhythm in the streetscape. Bicycle lanes, room for walking and the incorporation of still more trees."


:: image via Urban Omnibus

The concept of building retrofit has gained much attention, both as a economic necessity as building slows down, but also as shown in the article, the usable surface area of the city isn't just composed of the left-over terrestrial parcels, but a network of building faces, as cited in: " A recent New York Times article quantifies the amount of available roofspace in the city alone as 944 million square feet, 11.5% of the total building area the city holds."

Ignoring this resource will miss a significant opportunity to incorporate more area in our attempts to reforest cities, and also expand our toolkit beyond street tree canopy and dense planting in open spaces.