Langley Waterproofing Limited


Manufacturer: Langley Waterproofing Limited 

Materials: Poly Methyl Methacrylates (PMMA) 

Pararapide comprises the following components:

• Pararapide WP — a two-component polymethyl methacrylate waterproofing resin available in pebble grey (RAL 7032). Other RAL colours are available on request
• Pararapide WP Detailing — a thixotropic version of the standard resin, for use in detailing at upstands, corners, connections and other details, available in pebble grey (RAL 7032) and charcoal grey (RAL 7043). Other RAL colours are available on request
• Pararapide Fleece — a 1.10 kg·m–2 polyester fleece for use as a reinforcement
• Pararapide Asphalt Primer — a non-pigmented primer based on a two-component fast-reactive polymethyl methacrylate resin, for the preparation of asphaltic and bituminous substrates
• Pararapide Masonry Primer — a non-pigmented primer based on a two-component fast-reactive and fast-curing polymethyl methacrylate resin, for the preparation of absorbent substrates such as concrete, screeds and timber

BBA logo

Number: 16/5339
Issue date: 15/11/2018

Approved for use on

Flat Roofs Green Roofs Pitched Roofs Roof Gardens 

For use as a waterproofing system on flat and pitched roofs with limited access, including green roofs and roof gardens


Concrete Metal Plastic Reinforced Bituminous Membranes Timber 

On substrates of:
• concrete
• bituminous
• timber
• metal
• plastic

Surface Temperature Application

Installation should not be carried out during inclement weather (eg rain, fog or snow). When the temperature is below 5°C suitable precautions against surface condensation on the substrate must be taken. The substrate and ambient air temperature for the application of Pararapide WP standard formulation and Pararapide WP Detailing is between –5 and +35°C


25 Years 

Pararapide will achieve a service life in excess of 25 years.

Installation Requirements

The system should only be installed by installers who have been trained and approved by the Certificate holder.

Fire Safety

A system installed on a flat roof, comprising a 12 mm thick gypsum glassrock roof board, primed with Pararapide Masonry Primer and coated with Pararapide WP (grey) reinforced with Pararapide Fleece, will be unrestricted by the national Building Regulations.

In the opinion of the BBA, a roof garden incorporating the system, covered with a drainage layer of gravel 100 mm thick and a soil layer of minimum 300 mm thick, will be designated BROOF(t4).

In the opinion of the BBA, when the system is used in irrigated roof gardens, its use will be unrestricted under the requirements of the national Building Regulations.

If allowed to dry, plants used in a roof garden may allow flame spread across the roof. This should be taken into consideration when selecting suitable plants.

The designation of other specifications should be confirmed by: England and Wales — test or assessment in accordance with Approved Document B, Appendix A, clause A1. Scotland — test to conform to Mandatory Standard 2.8, clause 2.8.1(1)(2) (1) Technical Handbook (Domestic). (2) Technical Handbook (Non-Domestic). Northern Ireland — test or assessment by a UKAS-accredited laboratory, or an independent consultant with appropriate experience.

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Langley Waterproofing Limited

Lamport Drive
NN11 8YH

T : 01327 704778

E :

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