Sustainable Development

A terrace roof

It is always great finding in the middle of a city a little corner were you can find yourself in the nature

Published by Développement Durable the 2008-03-27
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Terrace roofs have a lot of benefits for environment and health. The ecological a health interest of the terrace roofs is overall related to the fixation of atmospheric dusts and pollen. Evapotranspiration breed by planted terraces raises humidity air levels and makes easier the dew’s creation which is essential for the dust fixation and pollens that are in the air. Lead and carbon particles, specific organic matter or low density organic matter are fixed in the substrate or they feed bacteria, plants and insects that develop. There is also a decrease of the CO and CO2 levels for the levels of oxygen produced.

Terrace roofs mean a growth of the available surface in a wild and natural, accessible or not environment. But it is can also become, if necessary, a leisure area which would lighten overloaded natural environments in diminishing traffic and noise. WE have also to speak about the benefits on climate, microclimates, hygrometry, and also for health and the welfare of inhabitants. Ecoroof let harvesting a part of the surface lost by the covering of the soil by buildings, by green spaces.

There are also lots of benefits for biodiversity. Wild life find their inhabitants and natural balance are recuperated. On the extensive green terraces, the most adapted plants are those from dry environment and oligotrophics. Precisely, these are endangered species because of a general eutrophication of environments. In this way, associate faunistic complexes find islands where it is possible their survival.

We can also be associated to an apiary in the green roof which permits the reintroduction of bees in the city. They are very important for plants pollination. It is like a reconstitution of a real ecological merge and corridors in the centre of the city. It allows the circulation of plant animal species but also the flux of genes which is very important for ht species survival and for their adaptation to environment.

Cities are always hooter than countryside. The excessive warming of roofs, concrete, street’s asphalt and the outsider masonry work warm in some degrees the environmental air.

Roofs are a 20% of our cities surface. Rain waters on roofs are immediately leaded to storm sewers. This overloads sewers and purification plants. Sometimes it causes subsoil floods. Like a sponge, a green roof stores water which parts are used for different things. One of its parts is for plants, another is evaporated and the last part is drained off a bit later through sewers so it permits a good flow.

Thanks to their capacity of harvesting, evaporation and salting-out from rainwater helps to fight against the harmful effects of soil waterproofing like the obstruction of sanitation networks in flood periods, influx of organic and metal pollutions after a storm, etc…

Yearly, a green roof can absorb until a 50% of the water that falls on roofs. It allows a reduction of water treatment costs from 5 to 10%.