Knightsbridge conversion creates a ‘hidden’ family home on a tricky super-prime plot

LTS Architects completes unique "Hidden House" project on Walton Street

Many residents of Knightsbridge like a bit of head-turning attention, but LTS Architects’ latest project is anything but ostentations, transforming two former workshop/retail buildings into one of the most subtle – and private – luxury pads in Prime Central London.

The family-sized redevelopment at 23 Walton Street is barely noticeable from street level, but still delivers a surprisingly airy three-bedroomed interior space, with a sort of industrial gallery feel.

Some tight planning constraints demanded some pretty ambitious architectural thinking, with an original building that could not be extended either upwards or outwards, and that offered little in the way of natural light or – initially – usable residential space.

Going underground was the only way forward, but that still threw up a wealth of challenges to ensure the finished property was light, liveable and not overlooked – and that works did not overly impact neighbours.

Solving many issues with one big design call, LTS created a pitched glazed roof, held together with laminated plywood beams that were prefabricated by a specialist joinery company. The team had to work within the constraints of the historic brickwork walls and engineer the structural beams so they would make the uneven, existing building appear balanced and symmetrical in the final space that was created. This design approach has transformed the internal areas into a very different space, which allows natural light to permeate the interior while maintaining visual privacy and defining the interior living areas.

A warm, light material palette of ash faced plywood, oak, exposed brick and bronze keeps things feeling modern, while the rooflights provide a flow of daylight and natural ventilation to the lower levels of the home, which includes two double bedrooms and a master bedroom with en-suite bathroom.

The L-shaped building retains its original external shape and dimensions, but interiors have been transformed into a sequence of seamless open-plan spaces, including a mezzanine study level tucked away within the roof pitch. To encourage light and air to flow through the lower levels of the property, including the deeper plan areas, LTS created a lightwell partially covered with a glass floor which allows light through the dining room floor and into the spaces beneath. To allow light and air to the basement bedrooms at the rear, a sunken courtyard garden provides further daylight, ventilation and some much-valued outside space.

Bedrooms are all on the lower level of the hidden home, with the master suite slightly secluded in the furthest corner. Some unusual architectural necessities have been pitched as historic features, with two original arched pavement vaults converted into the en-suite bathroom, allowing clever use of space as well as offering up some charming quirk.

Greg Shannon, Director at LTS Architects: “This has been a once in a lifetime project for everyone involved. Despite appearances, we have completely rebuilt and restructured the existing building to design the Hidden House and create a truly unique home for the owners. We hope it sets a new standard in design and demonstrates how we can make smaller homes beautiful and liveable by utilising space and light.”

Project team 

  • Architect: LTS Architects
  • Contractor: Broseley London
  • Structural Engineer: Engineers HRW
  • Building Services: SGA Consulting
  • Cost Consultant: Corrigan Gore & Street
  • Planning Consultant: Metropolis

In pictures