Excavation works started at the front of the house with the team tunnelling under the building by hand, installing supports as they worked, until there was a large enough area to install a conveyor belt to bring out the earth. A reinforced concrete floor was installed and each wall underpinned according to the engineer’s specification. Allowing for underfloor heating, insulation and floor screed the finished height of the excavated area was 2.4 M.
A light well was dug and reinforced with concrete to the front of the building and a bay window installed. A second light well to the rear of the basement was covered with Luxcrete blocks to allow light to pass through. As part of the sealed cavity drain membrane system, two Triton Aqua Pumps were installed to pump any water which might enter the basement into the perimeter Triton Aqua Channel which led to a natural drainage point in the light well and to the pumps. Isola Platon P5 membrane was fitted to the walls and heavier duty Isola Platon P20 laid to the floor. The London Cellar Conversion Company plasterboarded and skimmed the walls and installed an under floor heating system before laying a wooden floor. The new basement has provided an extra 90m² of living space which is divided into a large guest bedroom, shower room and WC, home cinema/play room, office area and storage.