Stop No. 14.1 Green Roof

Tiled roofs are monotonous, flat roofs are boring, green roofs are lively and beautiful.

1. Green roofs are aesthetically, economically, and ecologically viable

-          Green roofs are able to store rain water (plants and substratum can filter pollutants and heavy metals out of rainwater)

-          They reduce stormwater run-of, thus relieving the strain on the sewer system

-          They bring about the increase of humidity and, thus, have a positive effect on the microclimate of the surrounding area

-          They act as a sound absorber

-          They insulate the roof (cooling effect on hot days and heating effect on cold days)

-          They serve as a habitat for flora and fauna

-          In built-up areas, they contribute to restoring the contact between the underlying soil and the atmosphere

 

2. Flat roofs are ideal as a basis for green roofs

-          Green roofs have a lower risk of water penetrating through the roof structure than pebbled bitumen roofs

-          They have an increased roof life span

-          Roofs with an angle of inclination of up to 20° are unproblematic with regard to the  construction of green roofs

-          Roofs with an angle of inclination of 20°-30° must be secured with wooden beams or mats against landslides

 

3. Green roofs can be categorized as “intensive” or “extensive”, depending on the depth of the planting medium, the static equilibrium of the roof, and the amount of maintenance they need

-          An extensive green roof is designed to be virtually self-sustaining and should require only a minimum of maintenance. If the depth of the planting medium is app. 4 cm, the roof can grow simple plants such as moss, sedums, and houseleeks.

-          An intensive green roof requires a reasonable depth of soil (app. 10 cm) to grow large plants, conventional lawns, or even trees. They are labor-intensive, and require  irrigation, feeding, and other maintenance

 

4. There are several green roof systems from different manufacturers on the market

-          Example:

-          (Picture?)

 

 

-          A substratum mixture differs from normal substrata in weight and in the ability to absorb water; ideal substrata are those which are light and  able to store large amounts of water (e.g. lava, expanded clay pellets, etc.)

 

5.  If installed properly, green roof systems require only a minimum of maintenance

-          In most cases, it suffices to weed out wood seedlings

-          You can either plant or sow the soil on green roofs (e.g. sedums, houseleeks, or sowing of seeds). Sowing is the cheapest solution but is only recommended for flat roofs.

 

LBV: Susanne Schwab