When tasked to waterproof retaining structures in accordance with the British Standard 8102:2009, professional waterproofing designers should consider using more than one type of waterproofing to provide enhanced protection of the structure and to achieve the necessary environmental grade.
Above: Newton combined waterproofing systems were applied to the Hotel Football in Manchester as part of a complex waterproofing design.
The structure has no integral protection against water and relies on a membrane to be introduced internally or externally to prevent the ingress of water into the inner building fabric.
The structure itself is constructed to be integrally waterproof and the primary resistance against water ingress.
If water passes through the structure, it is depressurised and collected by the internal Cavity Drain System and then safely removed from the building.
Waterproofing Design Specialists are tasked to recommend a “combined“ waterproofing system approach particularly where:
The likelihood of leakage is high
The consequences of leakage are unacceptable
Additional vapour checks are necessary for a system where unacceptable water vapour transmission could otherwise occur
With this in mind, the possible combinations of waterproofing are
Type A, B & C
Type A & B
Type A & C or
Type B & C
Usually a combination of 2 forms of waterproofing is adequate when designing a habitable space requiring a completely dry internal environment, defined as ‘Grade 3’ within BS 8102:2009. Whichever combination of waterproofing is chosen to achieve the Grade 3 environment, in most cases the safest combination will include a 'Type C' internal cavity drain membrane system as one of the forms of waterproofing. The choice of the other system is largely dictated by the type of structure.
A typical combination waterproofing design showing Newton CDM Cavity Drain System internally (Type C), Newton HydroBond System externally (Type A), and Newton HydroTank System with waterbars and waterstops within the structure itself (Type B)
Newton highly recommend that installation is undertaken by a Newton Specialist Basement Contractor (NSBC). NSBCs can provide a meaningful insured guarantee and take full design liability on the project, fulfilling the role of ‘Waterproofing Specialist’ as recommended by the BS 8102:2009 ‘Code of Practice for Protection of Below Ground Structures Against Water From The Ground’. Please contact us for a list of NSBCs in your area.
Our staff are able to provide guidance for projects of all sizes, whether you require some general advice about damp or waterproofing, or support with technical drawings and specifications.
Newton Specialist Basement Contractors (NSBC) are an elite group of professional structural waterproofing and damp proofing specialists who work in partnership with us to provide clients with the best products, design and installation.