Luxury Eco House Development in the London Commuter Belt

When including a basement, developers can view a prospective building plot from a new perspective.

Developers are looking at more innovative ways to optimise available space and create stunning new houses for us to live in. Enhancing the building plot can make the difference to the project’s profitability.

Luxury self-build developer Datum Contracts & Construction had recently acquired a good-sized site in an excellent area ready for development. A challenge related to the site’s steep slope from the back to the front of the property. Straightforward excavation for the construction was not possible and a piled retaining wall had to be installed along both sides and the back of the site. Planning regulations had height restrictions for the build and building access was going to be a challenge. Datum realised that for this project to be successful they needed to exploit the slope and create an additional floor at basement level. The basement design incorporates the front door, living space and a good-sized double garage for each house, as well as space for storage and building services. Main living areas are accessed through the basement stairs.

One other challenge was to meet the expected insulation U-Values of 0.15, which is below Passive House standard, for the underground parts of the buildings. Datum creates super energy efficient houses and this means that all parts of the construction that are “underground” had to be encased in 200mm thick high-performance insulation, including under the foundation slab.

The importance of getting the basement right required a highly engineered precision solution based upon Glatthaar’s AquaSafe® basement system. Precast concrete panels and additional tanking of the external joints and walls delivered 100% protection against ground water penetration. The Glatthaar tanking system is an effective barrier against all forms of ground water, which is essential if the basement also includes living space.

Glatthaar’s prefabricated construction process meant that we were able to deliver the completed project to the client on schedule and within budget. Once the final plans are agreed, Glatthaar engineers the construction and manufacture the prefabricated basement elements in their German production plant. These are then delivered to site and installed by the Glatthaar UK installation crew.

The completed project aims to deliver stunning sustainable living, by utilising the sloped building plot to deliver a much-needed basement. Modern quality basements are a useful addition for any developer wishing to maximise their footprint and profitability.