March 3, 2016

Basement design in Chelsea has fast become the new extension for clients unable to extend outwards, thus they extend below ground. The GSE team have successfully carried out numerous basement designs over the last few years, working with various well known architects and specialist basement companies.

We recently completed a project with Lab Architects, a firm that we have worked with before on numerous occasions, to construct a 420m² basement complete with swimming pool in Chelsea, London. The architects wanted numerous large light wells to flood the new basement with natural light and ventilation, as well as substantial renovations and extensions to the house above ground.


A combination of piling and underpinning was used on this project to maximise the space achieved within the basement, but also working to the ground conditions onsite. Geotechnical investigations found that groundwater was present at depth and so secant piled wall was employed in the garden areas to limit groundwater ingress in those areas where the basement was deepest.

Under the house, where the basement was shallower and groundwater less likely to be encountered, reinforced concrete was underpinning was used. The underpinning maximised the space within the basement and so met the design brief.


The existing property on the site was extensively renovated and extended as part of the works. The whole building was supported at ground level in the temporary condition while the basement was formed underneath.

The GSE team undertook all the structural design of the permanent works for this project, working closely with the design team during the design development and with the contractor once they had been appointed. We visited the site regularly to oversee the Phase 1 works.


The team successfully delivered accurate structural designs on a project that had complex requirements and a tight deadline. The design brief was met and the end result an impressive, spacious, superstructure basement design in Chelsea.

At GSE we aim to provide excellent service through practical and effective structural design to facilitate each project being built. To speak with a member of our Award Winning team please get in touch.