Green Roof Water Retention

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Green roof water retention.

Our company offers consultancy and turnkey projects for green roof and terrace design landscape and long term maintenance in order to obtain the best results. Although there are no precise definitions of them an extensive green roof has a shallow growing medium usually less than six inches with a modest roof load limited plant diversity minimal watering requirements and is often not accessible. System solutions with defined water retention. Suitable for blue roofs.

We need to think differently about the main purpose of a green roof. Retention works like this. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. Figure 2 shows the daily rain and associated daily green roof runoff for 1993 in state college pa for a green roof having a maximum of 1 6 inches of water retention storage.

Rain falls onto a relatively dry green roof and the green roof absorbs the water usually in pore spaces later the sun comes out and the plants use the rainwater to evapotranspire. Green roofs typically provide stormwater retention as they capture water preventing water from draining and then allow the water to evaporate only through evapotranspiraton processes. Manufacturers whose materials we use for landscape works are well known all over the world. However a purple roof retains more water than any other green roof concept.

They fall into three main categories extensive intensive and semi intensive. Such an extensive green roof will have a water retention capacity up to 44 l m and a surface weight in water saturated condition about 130 kg m. The secret of green roof water retention is green. However retention is not always effective as it fills up the entire empty storage space in green roofs and then takes time to dry out and make room for new rainwater.

Note that there was very little if any runoff during the may 1 to sept 30 growing season. Discharge coefficient cs according to fll. Green roofs are also known as vegetative or eco roofs. The cuspate is overlaid by a bonded geotextile to prevent any blockages.

Water storage and discharge delay. Yes every green roof absorbs and buffers water. Drainage and water retention elements with low medium or high retention capacity are components of the green roof system. The purple roof is the only concept that has been exposed to real life assembled testing in a professional setting.

This means that the water leaves the roof as vapor. Geofabrics manufacture water retention and drainage boards designed specifically for living roofs.