CASE STUDY

Sika Watertight Concrete is helping to provide three storeys of living accommodation for a subterranean mansion in Kensington. This exciting project is being carried out by A.P.Arcon Construction, who are constructing a prestigious 6,230 ft2 dwelling on a strip of vacant land between two existing buildings. Although the bedrooms will be above ground, the main living areas will be underground, so total water-tightness is an essential requirement on the project.

Close to 1,000 cubic metres of Sika Watertight Concrete is being supplied by Hanson Concrete to create a watertight structure that will conform to BS8102 Grade 3 for habitable space. Around 1,200 skips of soil weighing around 10 tons each have been excavated to create the working space. With access being extremely limited, virtually the whole site had to be excavated by hand. Main piles up to 30 metres with soft piles up to seven metres in length had to be constructed on the project before excavation could begin. Particular care had to be taken to stabilise the adjoining properties as excavation progressed.

Sika Watertight Concrete is a high performance, cost effective solution in comparison to membranes and other systems. Time is saved at both the design and construction stages as the need for complex detailing and installation is eliminated. It also delivers the maximum usable area to the developer.

Sika Watertight Concrete is an ideal solution, especially in cities like London where space is at a premium, as the overdig requirement is kept to a minimum.

To complete the system, construction joints were sealed with the SikaSwell jointing system, which consists of joint sealing profiles that expand on contact with water to seal any voids between adjoining concrete slabs.

Jones Lambell Architects are responsible for the design of the building, and Clarke, Nicholls & Marcell are the structural engineers, acting for the client Gaugamela LLP. A two car garage and three main bedrooms with en-suite facilities will be completed above ground, with living areas, guest bedroom, swimming pool, cinema and various other rooms below.