Multi-phase Developments

Since CCL was formed in 1997, a core part of the company has been working on major multi-phase developments for leading building contractors across the United Kingdom.


CCL has built a tremendous reputation when it comes to completing the structural waterproofing, tanking, or ground gas proofing for many of the regional and national housebuilders, developers, groundwork contractors and architects.

In line with BS8102:2022, Code of practice for the ‘Protection of below ground structures against water ingress’ it states that an adequately qualified designer should be involved from the early design of the project. Cast Contracting Ltd (CCL) has several in-house CSSW qualified designers to accommodate the project-specific needs of a development.


To develop a robust design for protecting a structure against groundwater and ground gasses, CCL selects the appropriate gas or waterproofing measures, for example Type A, B or C protection and, where necessary, external drainage sheets. The results of site evaluation, including the hydrology of the site, is taken into consideration to ensure the appropriate waterproofing or gas design philosophy is adopted.

Peace of Mind

This may often include a combined approach to provide a ‘belt and braces’ solution, giving the client peace of mind that the design will stand up to the test of time and design life of the structure.

In addition to BS8102, CCL also follow:

  • BS 8485:2015+A1:2019 – Codes of practice for the design of protective measures for methane and carbon dioxide ground gases for new buildings
  • BRE 211:2015 – Radon: Guidance on protective measures for new buildings
  • Ciria (C735) – Good practice on the testing and verification of protection systems for buildings against hazardous ground gases

The vast majority of our multi-phase projects are not necessarily fully retained structures, so at CCL we need to consider the design, supply, and installation of the appropriate system. This is because it is more likely to be a sloping site, where you have multiple, semi-retained properties, or even interlinked property retaining walls, buried roof garages etc. Some of the schemes that CCL have worked on will be over the course of several years and implemented into hundreds of units.

Design Changes

As well as assisting with the initial design strategy, CCL will then engage with all the design changes throughout the project, which is common practice on multi-phase developments. This is to ensure the correct system is applied and the client obtains a watertight system, along with the corresponding requirements set by building warranty schemes such as NHBC, LABC and Premier.

Latest Projects

The Marshall Building, London

British Museum

The British Museum, London

St John at Hackney

St John’s Gardens, Hackney

Oxford Student Castle

Student Castle, Oxford

South Lodge Spa

South Lodge Hotel & Spa, Horsham

Sky Central

Sky Central

Sidney Sussex College

Sidney Sussex College Cambridge University

Royal Opera House

Royal Opera House Covent Garden

Paterson Building

Paterson Building, Manchester

CCL’s areas of expertise include

  • Design only schemes with CSSW designers
  • Water management systems
  • Damp-proof membranes
  • External membranes
  • Internal membranes
  • Cementitious systems
  • Injection systems
  • Podium membranes
  • Movement joints
  • Trafficable coatings
  • Carpark coatings
  • Balcony membranes
  • Wetroom systems
  • Bunded tanking
Multi-phase developments

Design | Supply | Installation

Cast Contracting Ltd (CCL) is the UK’s leading specialist in Design and Installation of all Waterproofing, Tanking and Ground Gas Systems across the United Kingdom. CCL prides itself on offering the highest level of service throughout the Design, Planning, and Installation process.

Structural Waterproofing & Ground Gas Solutions

CCL’s in-house design team can offer a comprehensive proposal for all scenarios in line with BS:8102 and BS:8485.

CCL Guarantees

One of the most comprehensive Guarantees across the industry, taking full project ownership.


Cast Contracting Limited is one of the longest standing industry specialists. As it is now part of the CCL Group of Companies, Cast Contracting Ltd has the additional stability and support with over sixty employees across the Group.

Our Services:

Working throughout the UK, CCL takes pride in offering the highest level of service with every major manufacturer across the sector.


Basement Waterproofing

Podiums / Terraces / Balconies

Ground Gas Membranes

Trafficable Coatings

Water Management System

External Membranes

Concrete Repair

Customer Success Stories

friars walk logo

★ ★ ★ ★ ★

Friars Walk

“The CCL team were incredibly conscientious and provided a 24-hour installation service to ensure our strict schedules were achieved. The team on site were very helpful and were able to provide solutions to overcome any problems encountered during the construction of the site. Nothing was too much trouble.”

Lee Lovering, Construction Manager, Bowmer and Kirkland

★ ★ ★ ★ ★

Royal Opera House

“Cast Contracting’s waterproofing expertise ensured that all of the critical waterproofing works carried out at The Royal Opera House were to the highest professional standard. The helpful and proactive team of applicators were able to deliver the waterproofing works to our strict installation programme whilst achieving a high quality of workmanship.”

Tom Ogden, Site Manager, Careys PLC

★ ★ ★ ★ ★

Grosvenor House

“Grosvenor House was a complex domestic build located on a site that was very wet. The subterranean ground conditions were running sand and a potential ground water pressure of 5 tonnes per square metre expected to the RC basement structure. With this in mind we needed to have complete confidence in the company who would be providing the water proofing solutions, which we found in CCL. From their initial proposals all the way through to completion they were professional, helpful, thorough and cost effective. It is imperative as a luxury house building company that you have a watertight structure below ground. Due to the CCL solutions and implementation, there have been no such issues that have arisen since completion and that is invaluable.”

Craig Riley, Contracts Manager, Charybdis Developments Ltd

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