contact Info

12th Floor, Capital House, 25 Chapel Street, London, NW1 5DH

+(44) 203 988 7994

The extension of a pre-existing basement to fulfil the original and intended scheme.    

Project overview

Scope of works



Structural Engineer:

Vincent Rymill


HBA Residential


24  weeks


Basement – 6,160 sq/ft 

Project Type:

Structures, Basement 


Share on facebook
Share on linkedin
Share on twitter
Share on pinterest

The Extension of a Pre-existing Basement

With a sizeable basement delivered by Knowles in 2018, we were pleased to have been recommissioned as Main Contractor by the new property owner at a super-prime residence on London’s exclusive Avenue Road.

In 2023, under the new ownership, Knowles’s scope of works involved the extension of the existing 1,750 sq/ft basement by a further 4,410 sq/ft, sitting beneath the 4-storey residence. This extension to the basement fulfilled the originally approved scheme.
With the basement now totalling an impressive 6,160 sq/ft, spanning the entire property footprint, the subterranean space now features a luxury swimming pool and spa, as well as further leisure and living facilities, discreetly housed beneath the super-prime home. As Main Contractor, works in our contract also included the reconfiguration of the ground floor, full internal strip out to deliver high-specification bespoke finishes, as well as extensive landscaping works.

Designed by HBA residential, the interior aesthetic reflects the new owners desire for a modern and luxurious family home.