Structural Waterproofing Guide
BS 8102:2009, The code of practice for the protection of below ground structures from water from the ground, defines three types of waterproofing systems - Type A, Type B and Type C. Any of these or a combination of two or more systems may be specified in a structural waterproofing project.
TYPE A Waterproofing
Comprises of various categories of barrier system that are applied to vertical or horizontal concrete and masonry.
FULLY BONDED SYSTEMS;
TWS-EX100 is a self-adhesive, very effective sheet membrane with unique selvedge for fast and secure seal on all side edge laps.
An easy to install water and water vapour barrier for use on foundations, basements, roofs, lift shafts and pits etc.
TWS-EX100 GM is a highly efficient, dual solution, self adhesive waterproofing membrane that also acts as a barrier against radon, methane, carbon dioxide and other ground gases.
LIQUID APPLIED SYSTEMS;
TT vapour membrane is a versatile, ready-blended waterproof coating that also acts as a barrier against methane and carbon dioxide.
TT55 is a cement 'tanking' system and highly effective as a damp proof membrane for brickwork, concrete or any cementitious substrate.
TT55 ME is a flexible water coating for use where vibration or cracking is anticipated.
TT Super is an 'active' formulation that migrates into the concrete to form a waterproof barrier but still allows the concrete to breathe.
TYPE B Waterproofing
Used for concrete waterproofing defined in BS 8102:2009 as where the structure itself is constructed as an integral water resistant shell. The water tightness of a Type B construction is reliant upon using a concrete of low permeability and appropriate joint detailing.
TT Admix is used at the time of batching. The chemicals react with fresh concrete to activley seal the concrete itself against the penertration of water or liquid and to protect it from harsh environmental conditions. Shrinkage cracks are constantly and automatically resealed during a life-long active protection system.
CEMflex VB Plate waterstop is a weatherproof, galvanised steel plate that only reacts with the water within the concrete and is therefore ideal for use in ICF or twin wall installations.
Waterstop is a hydrophilic, ready to use waterstop which swells up to 350% when in contact with water.
TYPE C Waterproofing
Defined in BS 8102:2009 as 'drained protection' which is achieved by the incorporation of a drained cavity within the new or existing basement structure. Water is collected in the cavity between the external wall and the cavity drain membrane and diverted to a suitable drainage point.
BBA approved P8 membrane is manufactured from tough, high density polyethylene and is impermeable to water, water vapour and radon gas.
BBA approved P20 membrane is an easy to use, high capacity drainage membrane typically used within the basement floor build up.
BBA approved Plaster Mesh features a mesh layer to create a mechanical key for direct plastering.
Double Drain is for external use and is designed to protect external basement walls from backfill damage. The filter fabric layer ensures soil cannot enter the membrane cavities to impede drainage therefore reducing external hydrostatic pressure.