What we keep: a survey before a scheme
Before drawing anything on an existing building we spend a fortnight recording what is already there. It changes the project more often than the brief does.
The most sustainable structure on any site is usually the one already standing. That sentence is now common enough to appear in tender documents, which means it is at risk of becoming decoration. The question that matters is narrower: which parts of what is standing are worth keeping, and how would you know?
The fortnight
On every reuse project we commit two weeks before design starts. No sketches, no massing, no concept. Just recording.
- Structure. What the frame actually is, not what the record drawings claim. Openings, previous alterations, where someone in 1987 cut a beam.
- Fabric condition. Moisture, movement, carbonation depth in concrete, mortar analysis in masonry. This is the part that decides feasibility, and it is the part most often skipped.
- Embodied carbon already spent. A rough figure for what it took to build the thing, so that demolition has to argue against a number rather than a feeling.
- What the building is good at. Floor-to-floor heights, daylight, thermal mass, the spans. Every existing building is unusually good at something. Find it before deciding what the new use will be.
The awkward finding
Roughly a third of the time, the survey says the honest answer is partial demolition. A 1970s deck slab at 2.4 m floor-to-floor with chloride-induced corrosion is not a building that wants to become housing, and pretending otherwise produces a bad project with a good press release.
Being willing to reach that conclusion is what makes the other two-thirds credible.
What we found last year
On a 1954 warehouse we expected to lose the roof structure entirely. The survey found the timber trusses were in better condition than the brick below them — a leaking parapet had been quietly destroying the wall head for thirty years while the roof stayed dry.
The scheme inverted. We kept every truss, rebuilt four metres of wall, and the building’s best room is now the one we had written off in the first week.
That is the argument for the fortnight. Not that it is virtuous, but that it is cheaper than being wrong in month nine.
Keep reading
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Materials Why we smoke oak instead of staining it
A stain sits on the surface and wears off unevenly. Smoking changes the timber all the way through. The difference shows up in year three.
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Light The four o'clock test
Most rooms are designed for noon and photographed at golden hour. We check them at four in the afternoon in November, when a room has nowhere to hide.