Waterproofing Board & Stud Drainage Board (HDPE / EVA)

Our waterproofing board (tunnel membrane) is a flat HDPE/EVA sheet used for waterproofing of tunnels, basements and underground structures, welded at overlaps with dual-track welding machines. The stud drainage board is a moulded HDPE sheet with hollow studs that create a continuous air/drainage gap, protected by a geotextile filter layer — it drains groundwater behind walls and under green roofs instead of letting it build up hydrostatic pressure.

Specifications

Waterproof Board Standard	GB/T 18173.1 (Polymer Waterproof Materials)
Drainage Board Standard	GB/T 17633 (Plastic Drainage Board)
Material	HDPE / EVA
Stud Height	8 – 25 mm
Compression Strength	≥300 kPa
Combo	+ nonwoven geotextile filter layer

Where Each Product Goes

• Tunnel waterproofing board: sprayed concrete primary lining → board → welded seams → secondary lining, creating a complete waterproof envelope.
• Basement wall drainage board: mounted on the retained wall, studs facing the wall, geotextile facing the soil — water drains down to the footing drain.
• Green roof drainage: placed above the root barrier to drain excess water while protecting the membrane.
• Road / railway subgrade drainage: stud board as vertical drainage layer beside the formation.

Selection Advice

• Choose stud height by expected water flow: 8–12mm for basement walls, 20mm+ for heavy groundwater or roof drainage
• Confirm compression strength against the overburden load (soil depth, wheel loads)
• The geotextile filter prevents soil fines from clogging the drainage channel — never omit it in soil contact