Site Specific: Secret Garden Flat

Nic Howett Architect - London, 2022

NHA Needing more space for our family, amidst unaffordable local property prices and with a reluctance to relocate, The Secret Garden Flat was self-built by us as an extension to our home. Situated behind a shop in a Victorian terrace on a busy high street in Camberwell, South London, the remodelling of this small, awkward ground-floor flat, has shifted the emphasis of living away from the front of the property towards the garden at the rear of the site.

Self-building, on a limited budget and with a palette of simple and modest materials that could be crafted with our own hands, we have added a new bedroom and a secluded garden studio where we can both work from home. The live/work arrangements of these new spaces are reflective of the neighbouring shops, workshops, commercial and residential buildings, providing discreet and sustainable additions to the building which is adjacent to a conservation area.

Access to the site is extremely difficult and this prompted our strategy for a utilising lightweight timber construction, with easily manageable cladding and lining elements, all sitting upon minimal concrete foundations. With our limited construction experience in mind the project was detailed simply and explored through drawings and models for a self build by ourselves, enabling us to rehearse the assembly of the structure in advance.

The garden studio was constructed first and acted as a test for the bedroom extension which came later. Replacing the balcony directly above the bedroom extension was a time-critical part of the construction process, with only a short period agreed for the flat above to be without their outside terrace. Constrained by the existing height of this structure thin vacuum panel insulation was required to minimise the thickness of the roof construction below. Additionally, a ‘build-over agreement’ with Thames Water had to be secured to build over drains shared by ourselves and neighbouring buildings.

Both the bedroom extension and garden studio have sedum roofs, as rainwater drainage connects to the existing sewer we were conscious of adding to this discharge. The sedum room prevents 75% of rainwater ever reaching the sewer. Limited steel is used in the construction of the extension and 95% is timber the garden studio is 100% timber. The use of concrete for the foundations is greatly reduced by creating lightweight structures that sit upon these. The timber cladding is cut to size from recycled larch boards and these were bought cheaply, costing £300 for both buildings. High performance glazing has been used in the expanses of glass, along with high levels of insulation throughout, the original front wall of the flat was also thermally upgraded to provide a warm home that is efficient to heat. 

The garden is large for our inner city location and was one of the main reasons we were drawn to the flat initially. By dividing the space typically used for a full width extension and shifting one half of this into the garden to create the studio, we have given ourselves two new structures and also created an intimate garden space in-between; the sum of the parts is more than the whole. These new additions now sit comfortably amongst the palimpsest of alterations and ad-hoc developments of the neighbouring buildings. The end result is a flexible home we hope to enjoy for years to come.

NOTES

Thanks to Nic Howett for sharing this project for us. Click here for more work from Nic Howett Architect.

Completion photographs © Henry Woide.

Posted 24th February 2023.