Waterproofing and Building Membranes

The BBA is the UK's leading authority on the testing and assessment of new building membrane systems and materials and has built up an unrivalled expertise in the testing of many of these, including:

 Roof Waterproofing

 Damp-proof membranes

 Damp-proof courses

 Roof-tile underlays

 Breather membranes

 Bridge deck waterproofing systems

 Rail Bridge waterproofing systems

An example of a roof membrane that failed during

wind loading.

Resistance to wind loading

A unique rig, BBA TEMPEST, is available for the testing for resistance to wind uplift of roofing membranes. Using roof mock-ups of up to 3 m by 3 m, so large insulation boards or widely spaced mechanical fixings can be placed at centres reflecting use in the real world.

Originally designed to perform wind-loading test on roofing membranes this equipment can also be used to measure the wind-load resistance of vertical elements such as claddings and external insulation systems.

Most tests are described in BBA MOAT No 55 : 1991 UEAtc Supplementary guide for the assessment of mechanically fastened roof waterproofing and in BBA MOAT No 50 : 1992 Technical guidelines for the assessment of thermal insulation systems intended for supporting waterproofing coverings on flat and sloping roofs. Both documents require a series of stylised windstorms to be applied. Each of these incorporates 1415 gusts and lasts approximately three hours. Testing begins with a peak load of 300 N per fastener or 1.0 kPa for bonded systems and is then increased in 100 N or 0.5 kPa increments, respectively.