Underground mansion watertight concrete system

Watertight concrete system

The use of Hanson Watertight concrete has enabled A P Arcon Construction Ltd to construct an exciting new, partly subterranean mansion, on a strip of vacant land between two existing buildings in Kensington.

The main bedrooms, entrance and garage space are above ground, but the main living, entertainment and swimming pool areas are underground, so total watertightness was an essential requirement on the project. For this reason, A P Arcon chose the Hanson Watertight concrete system to construct the below ground shell of the building.

Close to 1,000 cubic metres of Hanson Watertight concrete were supplied by Hanson Concrete to create a watertight structure that conforms to BS8102 Grade 3 for habitable space. Around 1,200 skips of soil weighing around 10 tons each had to be 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.

Hanson Watertight concrete is a high performance, cost effective solution, saving time at both the design and construction stages, and it also delivers the maximum usable area to the developer, as the overdig requirement is much reduced. This is an important feature on projects such as this in cities where space is at a premium.

Arek Palka, Director at A P Arcon commented: “We chose the Hanson Watertight concrete system for a number of reasons, including a 50 year track record, a competitive price and warranty. Importantly, Sika supplied good technical back up throughout which gave us added reassurance on such a complex and difficult project”.

The project is now complete, with a two-car garage and three main bedrooms with en-suite facilities above ground, together with living areas, guest bedroom, swimming pool, cinema and various other rooms below.

Watertight concrete system

  • A P Arcon Construction Ltd

    Contractor

  • Hanson Watertight concrete

    Material

  • 2015

    Completion

Location

Kensington
SW7 1AA Kensington (United Kingdom)