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ARDEX WeldTec Tanking System

ARDEX WPM 1500 is a pre-applied, fleece-lined, weldable waterproofing membrane for below ground tanking and gas barrier applications. ARDEX WPM 1500 is welded at laps and seams to create a strong, continuous waterproofing membrane.

  • Protection Board: ARDEX DRS 10 GC
  • Waterproofing: ARDEX WPM 1500
Key Features
  • Proven butyl long term performance
  • Allows maximum use of confined space
  • Radon, hydrogen sulphide and methane gas barrier
  • Not reliant on confining pressures, hydration or tape systems
  • WeldTec technology to create very strong, watertight laps and detailing
  • Forms a unique, continuous waterproofing membrane
  • High elongation — excellent crack bridging capabilities
  • Excellent bond strength to concrete to ensure waterproofing
  • Excellent water migration resistance
  • Manufactured in New Zealand 
NZ Made
NZ Made
Scope of Use

ARDEX WPM 1500 is normally used as a single layer membrane in horizontal or vertical applications for waterproofing in below ground applications. It is primarily applied to the outside of a sub-structure of a building, such as a foundation or basement, to prevent water ingress or as a gas barrier to prevent the ingress of toxic gases.

ARDEX WPM 1500 can also be used in other applications including: 

  • Under floor slabs
  • Behind masonry walls
  • The lining of substrates of in-situ or precast concrete
  • Retaining walls
  • Lift shafts
  • Tunnels

ARDEX WPM 1500 can also be used in combination with other ARDEX WeldTec products. ARDEX WPM 1500 may be used in various combinations to produce a variety of specifications tailored to suit the individual waterproofing needs.

Limitations on Use
  • ARDEX WPM 1500 must be protected from UV once installed. Maximum exposure should not exceed 60 days
  • Not suitable as a trafficable surface
  • Must be installed to the ARDEX technical literature
  • Must be installed by an ARDEX approved installer
  • Construction joints must be adequately detailed
  • Top edge must be terminated mechanically and sealed
Statement of Building Code Compliance
  • B2 DURABILITY: Performance B2.3.1(a) Not less than 50 Years ARDEX WPM 1500 is a suitable material for tanking (Butyl) and is expected to have a minimum life of 50 years provided it is installed in accordance with the technical literature.
  • E2 EXTERNAL MOISTURE: Performance E2.3.3 Walls, floors, and structural elements in contact with, or in close proximity to, the ground must not absorb or transmit moisture in quantities that could cause undue dampness, damage to building elements, or both.
    ARDEX WPM 1500 is considered impervious and has been independently verified to have a vapour flow resistance greater than 1700 MN s/g NZS 3604:2011 and NZS 4229:2013 require DPMs to have a vapour flow resistance of no less than 90 MN s/g
  • F2 HAZARDOUS BUILDING MATERIALS: Performance F2.3.1 Materials must not present a health risk to people. ARDEX WPM 1500 is inert and meets this requirement. Note: Basement designs solutions must be considered and alternative solutions- they are not covered by NZBC E2/AS1
Other Performance Attributes


Test Report DC 2428

  • AS/NZS 4201.6 Water absorption
  • ASTM E96 Water vapour transmission

Test Report DC 2893/6

All tests applicable to AS 4654.1 including:

  • ASTM D6207 Dimensional stability
  • AS/NZS 4858 Heat Ageing
  • CSIRO Moving joint test-Cyclic Movement
  • AS 4654.1 Table A4 Temperature resistance, tensile strength and durability


Test Report 1318

  • DIN 53380/ISO15105 Gas Permeability-Methane


Test report PN 138333-A/138333-B

  • ASTM D1434-82 Procedure V
  • ASTM D471-12A Gas permeability- Hydrogen Sulphide


Test report 124023/2016

  • K124/02/95 Radon diffusion coefficient
  • The above test reports are available on request and upon completion of signing a confidentiality contract.
B2 Durability compliant
E2 External Moisture compliant
External Moisture
F2 Hazardous Building Materials compliant
Hazardous Building Materials
Product Info: ARDEX DRS 10 GC
Product Info: ARDEX WPM 1500
Substrate Specification
BRANZ Appraisal 1126: WPM 1500

1126 [2021]

Maintenance Instructions
Brochure: ARDEX WeldTec
ARDEX Company Profile

ARDEX New Zealand supply and manufacture a range of quality construction materials, including products for levelling floors; external and internal waterproofing; and fixing natural stone and tiles.

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