Private Client


This secluded, detached post-war house, originally designed by Burns-Guthrie around 1969-1970 in a mid-century modernist style is reminiscent of Casa de Vidro by Lina Bo Barda. A hidden gem at the edge of a conservation area in Tunbridge Wells the partially cantilevered, partially buried house sits on a steeply sloped site within a generous plot surrounded by mature trees, some of which are protected with TPOs,  forming part of a historical woodland. The house is totally concealed from the main road, accessed via a steeply sloping driveway. Upon arrival one is met by the gleaming white rendered example of later modernism.


Tasked with expanding the house to accommodate their large wider family we sought to optimise the most of a large flat roof that providing breath-taking views out across the valley below. In order to facilitate the vertical expansion, the whole interior on the ground floor is to be fully reconfigured to enable each space to function more efficiently and as per the client’s brief, is to reflect their lifestyle for open entertaining Other external alterations to the existing house are required to rectify unsympathetic modifications and to better reinforce and restore the underlying modernist principles of simplicity, clean lines and a clear composition of forms.


In order to help minimise the impact of the rooftop addition and to retain the strong geometry of the cantilevered upper level, the new structure is set back on all sides except within the internal courtyard where the use of double-height glazing connects the old and the new. A couple of elements, including the chimney and new cylindrical staircase enclosure, are accentuated by increasing their height providing a counterbalance to each other as well as variation across the façade. These elements are mainly visible on the south elevation where the visual scale of the property is reduced, due to the change in levels across the site. The tall glazing on this side is limited to 4m with the upper portion set back to again reduce the impact on the courtyard.


Although a clearly contemporary addition the rooftop will be a combination of slimline glazed windows with the external façade, clad in black-stained timber allowing it to remain subtly nestled among the mature trees, allowing the strong, white geometry of the house to retain its clear dominance and appeal.


Forming a strong base on which the larger box form sits the lower floor is to be clad in tiles reminiscent in shape and colours to many mid-century properties. Existing windows and doors are to be replaced to provide a coherent appearance to modernise and improve the overall aesthetic of the house.


Due to its original cantilevered upper level, the proposed scheme requires some clever planning to prevent overloading the hard-working structure. The insertion of new columns and bridging structures will be required to transfer loads where they can be dissipated to the ground below.



Project services provided –


Feasibility Study

Concept Design

Planning Submission

Discharge Planning Conditions

Detailed / Technical Design

Manage Tender Process

Construction Drawings

Site Attendance during Construction

Contract Administration

As-Built Drawings



Design Team.

Foster Structures – Structural

Compliance BC – Approved Inspector


Detailed Design. May 2021