Green Roof Drainage Plan

Green roofs are designed to intercept and retain precipitation reducing the volume of runoff and attenuating peak flows.

Green roof drainage plan.

Z110 green roof drain shown with 18 height for intensive green roofing applications. The grs gr52 panel size is 24 x 24 x 2 125. Secondary overflow drains are located at a higher point on the roof. Flow of water into them is promoted by positive drainage.

Intensive layered green roof intensive green roofs have a deeper soil depth therefore the roof drain enclosure height is typically 12 or more. It is made of a filtration veil and the polyamide monofilament fibre network layer. Green roof solutions gr32 and gr52 drainage panels come in 24 x 24 interlocking squares constructed of 100 recycled high density polypropylene hdpp. Drainage protection filtration layer it is used for lightweight green roofs terraces and has many functions.

Bauder sdf drainage layer. Protection drainage and filtration. The filter layer on a green roof is designed to prevent soil and other substrates as well as debris from filling the cavities of the drainage membrane. The gr52 can withstand 0 352 gallons per square foot or 1 4 gallons per panel.

Dead and imposed loads should be calculated in accordance with bs en 1991 1 1 be en 1991 1 3 and bs en 1991 1 4 and should include the weight of the waterproofing system saturated weight of the green roof components and substrate vegetation snow loads and imposed loads such as access by people and vehicles as well as point loads for. Urbanscape extensive inclined up to 20 and pitched green roof systems 20 45. For flat or nearly flat roofs primary drains are located at the lowest point of the roof. The roof is likely to consist of an impermeable layer a susbstrate or growing medium and a drainage layer although not all green roofs require a drainage layer.

A green roof may require a separately plumbed secondary drainage system also known as the overflow relief system.