Gianni Botsford Architects designs a dramatic oculus for Notting Hill home

The project House in a Garden builds on Gianni Botsford’s earlier preoccupations with the manipulation of natural light throughout the day and through the seasons, enriching, enlivening and, ultimately, defining the nature of the architecture. Botsford is the Director and Head of Design at the Gianni Botsford Architects (GBA), which he set up in 1996 in London.

Botsford describes the house, “To build with light and darkness is to work with what a context gives you - a unique set of constraints and opportunities. Shaped and informed by the light and shadow that surround it, the roof’s tent like form creates a new place for life to occur in the house - one that turns its back on the large volumes surrounding it and embraces the site.”

Interestingly, GBA was his own client for the design of the house in London. “House in a Garden began in 2007 on a back-land site, immediately adjacent to my own apartment. A flat roofed bungalow had been built on the site in the 1960s and I had spent much time observing how the sunlight affected the bungalow and its garden, before eventually buying the site, and developing my own self-initiated proposal for a replacement dwelling as a prospective development,” mentions Botsford. However, after the planning stage, the project was purchased by a client who remained relatively hands-off during the construction period.

The key move was understanding how to harness the sun in a north facing context that is surrounded by five-storey buildings, and the dominant roof form of House in a Garden is a reflection of this in allowing sunlight to penetrate into the main living space and surrounding courtyard gardens. – Gianni Botsford

Externally the most visible component of the house, based in London’s upscale district Notting Hill, is its funnel like copper-clad roof. Inside, the roof comprises a complex glulam timber structure made from spruce, its double curvature concluding in a glazed oculus. The form of the roof is such that it enhances a sense of lightness while connecting the interior of the house to the surrounding landscaped garden as well as to its urban context.

However, Botsford believes that the project has more striking features than just the roof. “The house isn’t only about the roof, however. There are two subterranean floors below the ground floor, the living room, which also benefit from the forensic analysis of the site, receiving light and gaining views of the sky via lightwells and internal courtyards,” he said.

The house clearly provides an unusual experience in London, where sites are otherwise often restricted. Because of its subterranean design, the ground level is akin to arriving on a rooftop, surrounded by tall buildings, and yet with a genuine sense of tranquility and privacy.

Copper recurs throughout the house, in surfaces of the ground floor kitchen and in detailing of rooms below, adding a subtle tonal warmth to the interior. As a natural material, copper resonates well with the idea of much of the house being shaped underground. It also reflects light. There are two levels below the ground floor. Bedrooms are immediately below ground, while there is a generous living and gallery area with a 10-metre-long swimming pool on a level further below.

The project provides a useful companion to architectural methodology showing how careful site analysis can produce strikingly different results. “Mapping often has a binary relationship with architecture; what gets built looks like the map, but our process transcends the data that underpins it by having no stylistic preconceptions yet with the same focused application of an idea,” adds Botsford.

Details are not where we start. Materials are not where we start. We start by analysing a site forensically to determine how the form and organisation of the project should adapt locally to the climate, culture and context. – Gianni Botsford

Todd Longstaffe-Gowan, the landscape architect of the project, describes the design, “The Garden House, as its name implies, lies within a leafy oasis – one so secluded and so concealed that it evokes the charm of a remote rural sanctuary. The house is approached from the street through an opening in a privet hedge. This winding path in turn leads to a gate, which opens to a boardwalk set in a canyon-like corridor flanked on both sides by bamboo grasses and ferns. Here the house erupts from the ground, crowned by a copper tented roof. The entrance court has a single tree - a London plane - and drifts of bamboo under-planted with many intriguing creepers, plants, bushes and shrubs.”

The architecture and design teams went through brainstorming sessions to ensure that the final outcome was a result of careful exploration of the site and a rigorous methodology. They dealt with questions and thoughts like, “How does a concrete wall hit the ground?”, “How do you show how the roof is spanning?”, “Do we want it to feel heavy or light?”, and “Each line is important and cannot be ignored. Each line has a meaning and represents extraordinary things.”

Lightwells and skylights are designed to optimise daylight casting toplight onto the walls of lower ground floors. Introducing daylight to a depth of up to eight metres was a challenge, especially as the site of the house is tight and north facing. Digital analysis tools were used to seek out the three-dimensional possibilities that light gives in terms of generating the form and organisation of the building.

“We work in three dimensions, and think in three dimensions to create our details using physical models, computer models and full scale mock-ups. Each detail comes from a holistic understanding of how each junction meets, and what the various hierarchies are. Each detail is drawn as a future possibility for a project that one never really knows whether it will be realised. The translation to the actual from the virtual is a whole other level as one overcomes all the issues that construction throws at you. But as humans we are there to solve problems and find solutions together and this is where beauty lies,” concludes Botsford.

Project Details

Name of the project: House in a Garden
Location: London, England
Design: 2007-2014
Planning: 2008
Construction: 2014-2018
Plot size: 256 sqm (2,752 sqft)
Gross internal area: 253 sqm (2,722 sqft)
Architect: Gianni Botsford Architects (Gianni Botsford, Paulo Martinho (Project Architect), Kate Darby, James Eagle, Hiroshi Takeyama, Anahi Copponex)
Structural engineer: Built
Services engineer: Pearce and Associates
Landscape architect: Todd Longstaffe-Gowan