Drainage board also call plastic drainage sheet is a type of green roofing and foundation driange systems which are drained by a special molding plastic sheets. Water is retained and drained off within dimple on the upper sides of the drainage board; excess water spills over the edges of the plates and is carried off from the roof or foundations. The plastic or HDPE drainage board are made from HDPE(high-density polyethylene), using high pressure to inject plastic to form hole-lump-shaped shell, with stereo space and support level; in the top of the shell, covering with non-woven as filtering level for water percolation, water storage and water drainage. Application scope 1. Greening project: the garage roof greening, roof garden, vertical greening, roof greening, football pitches, golf course, etc. 2. Municipal engineering: airport, road embankment, subway, tunnel, landfill, etc. 3. Construction: the upper or lower building foundation, inside and outside the basement wall, floor and roof, roof seepage control and heat insulation layer, etc. 4. Water conservancy project: the reservoir seepage water, reservoir, lake water seepage control, etc. 5. Traffic engineering: highway, railway basement, roadbed, dam and slope protection layer, etc
