single solution was needed to overcome all the problems. A cavity
drain membrane was installed to the walls of the affected area, stretched
diagonally across the soffit (using metal fast track battening to support
the soffit membrane and prevent bulging) in order to catch any further
seepage through the pavement lights. An internal peripheral drainage
channel was set into the slab at the wall/floor junction to drain all the
collected water into a sump chamber, which had a dual pumping system and
alarm. The collected water was then pumped out up to ground floor level
into the existing drainage system.
completion of the works and following a routine visit to the store during
torrential rain, the pumps were removing significant amounts of water,
leaving the store completely dry. Previously that amount of rain would
have resulted in several millimetres of standing water in the basement
section of the shop.