Home > Companies > Langley Waterproofing Systems Ltd > PC-20 W Paracoat Liquid Roofing System

A single pack, warm roof, cold-applied high performance polyurethane waterproofing system for flat or sloping roofs, with a skid resistant finish.

Features and benefits:

  • Robust.
  • Seamless and flexible.
  • Includes reinforcement with a glass fibre fleece.
  • Permanently elastomeric.
  • UV resistant.
  • Life expectancy of approximately 30-years.
  • Cold applied, heat/ flame free application, with a self-adhesive vapour barrier and carrier membrane.
  • Quick and easy to install, with no on-site mixing required.
  • Manufactured in accordance with BS 476: Part 3: 2004, and EN 13501-5: 2005.
  • BBA certified.
  • Comes with a 20-year independently insured guarantee for materials and workmanship, which may be extended to a 25-year guarantee with an additional top coat (only valid when installed by approved contractors).


  • Preparation: Langley Primer.
  • Carrier membrane: Paratene self-adhesive bituminous membrane (0.6 kg/m²).
  • Insulation: Parafoam Ultra PIR Insulation (4.48 kg/m²).
  • Liquid applied waterproof coating: Paracoat Top Coat (0.75 kg/m²) and Paracoat Base Coat (1 kg/m²) polyurethane waterproof coatings.
  • Waterproof coating reinforcement: Langley Glass Fibre Embedment Fleece (0.225 kg/m²).
  • Vapour control layer: Paratene self-adhesive bituminous membrane (0.6 kg/m²).


Suitable for use on flat or sloping roofs in refurbishment or new build projects. Can be used on all roof deck types.

Timber board roofs will require a nailed attachment layer in accordance with BS 8747: 2007 before application.

System accessories include biocidal wash, specialist primers, rooflights, flashings, refurbishment outlets, vents, and edge trims (specified separately). Consult manufacturer for further details.

Standard product features




Dark grey.


  • Carrier membrane/ vapour control layer: 0.6 mm.
  • Insulation: 120 mm.
  • Top and base coat: 1.5 mm.


7.655 kg/m².

Technical characteristics:

  • Fire performance: Broof [t4].
  • Curing time: 8 hours/ coat.
  • Elongation: 500% (un-reinforced).
  • Shear strength: 98.7 N.
  • Slip resistance: Dry: 0.88; wet: 0.21.
  • Tensile strength: 11.5 N/mm².

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
20-50-30/140 Liquid applied warm roof covering system

NBS Specification

NBS Buliding logo
This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Langley Waterproofing Systems Ltd


+44 (0)1327 704778

Product reference

PC-20 W Paracoat Liquid Roofing System

Surface treatment

[Not required]
[Skid-inhibiting finish]
For use on walkways, maintenance areas and fire escape routes.

Manufacturer details

Langley House,
Lamport Drive,
Heartlands Business Park,
Northamptonshire, NN11 8YH
Tel +44 (0)1327 704778
Fax +44 (0)1327 704845
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