cavity membrane

Background

As part of the refurbishment of one of the finest townhouses in Central London, staff accommodation in the garden flat was included in the refit. The highest standards of specification were used throughout the building, and this dictated the use of the ADD Waterproofing system to provide combined control of both water and radon gas. The recently published BS8102:2009 requires radon to be taken into account during the design and installation of all basement waterproofing schemes.

Works carried out

ProTen Services’ specially-trained technicians installed the ADD Waterproofing system in the lower-ground floor rooms.

Cavity drain membranes were fixed to the walls, and a sump chamber was created to house a pump system to evacuate water. This method of waterproofing is now the preferred way to achieve waterproofing to the British Standard, BS8102:2009.

To protect the garden flat (and the rooms above) from radon entry, the mechanical elements of the ADD Waterproofing system were installed, including a precisely calibrated air management unit which also introduces positive pressure. This unit also controls the humidity levels within the flat. These and other mechanical elements were housed within a built-in cupboard faced with a grille, so there was little impact to the aesthetic appearance of the room.

Results

Once the ADD Waterproofing system had been installed, the walls were plastered in a conventional manner, and the rooms decorated and furnished. Subsequent laboratory testing was carried out, and the results showed that the radon level inside the property was well below the recommended maximum level for domestic properties. The rooms were left dry, and more importantly, safe for the occupant to use.