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Sika Sikaplan WP 1120-20HL

Sika Sikaplan WP 1120-20HL

📋 Product specifications are for reference only.

All product details should refer to the official manufacturer documents. For official product data sheets or technical enquiries, please contact us via WhatsApp.


Sikaplan® WP 1120-20 HL — PVC Waterproofing Membrane for Underground Structures

Sikaplan® WP 1120-20 HL is a homogeneous PVC-P (polyvinylchloride) sheet waterproofing membrane with a yellow signal layer, designed for waterproofing tunnels, basements, shafts, and all kinds of below-ground structures against groundwater. The 2.0 mm thick membrane is installed by loose laying, mechanical fastening, or ballasting, with all overlaps heat welded. Installation must be carried out by Sika-trained contractors.

Key Features

  • Virgin PVC-P material — consistent quality homogeneous sheet
  • Yellow signal layer to indicate membrane damage during inspection
  • High tensile strength: MD 17.0 / CMD high strength (EN 12311-2)
  • High elongation: ≥ in both directions
  • Tear strength ≥ 500 N (nail shank, EN 12310-1)
  • Foldable at low temperatures down to
  • Resistant to natural aggressive mediums in ground water and soil
  • High mechanical impact resistance ≥ 750 mm (EN 12691)
  • Dimensional stability ≤ change after heat (EN 1107-2)
  • Can be installed on damp and weak substrates
  • Eco-Product Directory listed (Application No: PL-00975-2021)

Applications

  • Tunnel waterproofing (including cut and cover tunnels)
  • Basement and below-ground structure waterproofing
  • Shaft waterproofing
  • Protection against groundwater ingress

Technical Specifications

PropertyValueStandard
Material BasePVC-P (homogeneous sheet)
Overall Thickness2.0 mm (-5/+)EN 1849-2
Mass per Unit Area~ (-5/+)EN 1849-2
Roll Dimensions2.0 m (W) × 15.0 m (L)
Roll Weight~78 kg
Tensile Strength (MD / CMD)17.0 (±2.0) / 16.0 (±2.0) N/mm²EN 12311-2
Elongation (MD / CMD)≥ / ≥ EN 12311-2
Tear Strength (Nail Shank)≥ 500 NEN 12310-1
Impact Resistance≥ 750 mmEN 12691
Static Load Resistance≥ 20 kgEN 12730 Method B
Foldability at Low TemperatureEN 495-5
Water TightnessPassEN 1928 B
Dimensional Change After HeatEN 1107-2
Reaction to FireClass EEN 13501-1
Exposure to BitumenNo performance determinedEN 1548
Application Temperaturewide temperature range
Shelf Life5 years (unopened, original packaging)

Limitations

  • Installation by Sika-trained contractors only
  • Not UV stabilized — cannot be permanently exposed to sunlight
  • Not resistant to permanent contact with bitumen or non-PVC plastics; separation layer (PP geotextile ≥ ) required
  • Special precautions required below or above RH
  • Ensure adequate ventilation when heat welding in enclosed spaces

FAQ

Can Sikaplan WP 1120-20HL be used for rooftop or exterior waterproofing?

No. This product is designed exclusively for underground structures (tunnels, basements, shafts). It is not UV stabilized and cannot be permanently exposed to sunlight. Use other Sika waterproofing products for exposed applications.

How are the membrane sheets joined?

All overlaps must be heat welded using hand welding guns (e.g., Leister Triac PID) or automatic machines (e.g., Leister Twinny S / Triac Drive). Welding parameters must be established through on-site trials before production welding. T-joints require special preparation with chamfered overlaps.

Can it be installed on a damp substrate?

Yes. Sikaplan WP 1120-20HL can be installed on damp substrates, which is one of its key advantages. Installation methods include loose laying, mechanical fastening, or ballasting as appropriate.

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