Installing internal and external structural waterproofing solutions

A waterproofing solution was required for a substantial new build basement in Pulborough, West Sussex.

Newton Specialist Waterproofing Contractor Cast Contracting Ltd (CCL) were awarded this prestigious project by Adam Architecture and main contractor RW Armstrong, with the task of supplying and installing comprehensive internal and external structural waterproofing solutions in order to prevent the ingress of ground water into the concrete basement structure.


CCL specified and installed the self healing, hydrophilic Newton 403 HydroBond membrane beneath the basement slab before applying the seamless rubber waterproofing membrane Newton 109-LM to the external surface of the walls as well as the terrace area above, linking to the Newton 403 HydroBond membrane and terminating at DPC level.

The Newton 410 GeoDrain drainage layer was then installed directly in front of the Newton 109-LM in order to protect the membrane during backfilling and promote the dtrainage of water away from the structure and towards the installed land drain.

Newton 503 and 508 cavity drain membranes were also installed to the internal walls and floor respectively, in association with the 50mm closed-cell insulation board Newton Fibran XPS 500-C. Perimter Basedrain channels, and a suitably located Titan Pro-White sump chamber completed the cvavity drainage system in order to fully ensure that any ingressing water was quickly collected and discharged.

Finally, Newton 408 DeckDrain and 409 Root Barrier were installed above the terrace to provide full protection prior to the final landscaping works.

  • A blockwork lining wall was constructed internally inside the full System 500 cavity drainage membrane.

  • Newton 409 RootBarrier was installed as a final line of protection beneath the above-ground landscaping.

  • Newton 403 HydroBond and 109-LM combined to provide continuous external waterproofing protection.


By combining both Type A and Type C waterproofing, CCL installed combination waterproofing that conforms with the recommendations of BS 8102:2009 in order to effectively protect this luxury basement.

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