The brief was three bedrooms, a hot climate, a tight budget, and a request the architect quoted back to us verbatim: “somewhere to sit outside that isn’t unbearable in August.”
The answer was to build a roof first and then work out how much of it to enclose. The enclosed part came to 94 square metres. The roof covers 210. What happens in the difference is most of what makes the house work.
The structure is the plan
The roof is carried on eleven glue-laminated beams at 2.4 metre centres, spanning 9 metres, with a 3 metre cantilever at the south edge. That single decision fixes almost everything downstream.
Because the beams span the full width, none of the internal walls is structural. The plan was drawn — and has already been changed once by the occupants — without touching a beam. Because the cantilever is 3 metres, the south glazing sits in shade from about ten in the morning until late afternoon at that latitude, without a single external blind or shutter.
And because the beams are exposed, the ceiling is the structure. There is no plasterboard, no service void, and no reflected ceiling plan. Services run in a floor spine and up two vertical chases, which is a discipline rather than a convenience: adding a light fitting anywhere else means a surface-mounted cable, and the occupants have accepted that trade.
The gutter is the hardest part
A big roof with a deep overhang moves a lot of water, and the detail at the edge is where these projects usually fail.
Here the beams stop short of a continuous edge beam, and the gutter sits behind it — a concealed gutter, which is the risky choice. Concealed gutters block, and when they block they discharge into the building rather than off it. The mitigations are all visible in the drawings and worth listing, because they are what makes the detail defensible:
- The gutter is oversized by roughly 60 per cent against the calculated flow, so a partial blockage does not overtop.
- There are two overflow spouts through the edge beam, deliberately expressed, that will stain the timber if they ever run. That stain is the maintenance alarm.
- The membrane is dressed up the back of the edge beam to 150mm above the gutter invert, so an overtopping event goes outward rather than inward.
- The gutter is accessible from the roof plane without a ladder against the fascia.
None of that is expensive. All of it is the difference between a detail that works for thirty years and one that works until the first autumn.
What the unenclosed area is for
Calling the covered outdoor space a veranda undersells it. In practice it is three rooms without walls, and the occupants use them by time of day: the east end for breakfast, the middle as a workshop and drying area, the west end in the evening.
The reason it works, and the reason so many covered terraces do not, is that it is deep enough. At 3 metres of cover you can put a table under it and still be dry in driving rain. At the 1.5 metres more commonly built, you get a wet table and a strip of shade that moves off the seating by mid-morning.
Depth of overhang is one of those figures that reads as excessive on a plan and modest in use. It also happens to be the cheapest square metres in the whole project, since there is no floor build-up, no facade, and no services.
The number the client cared about
The house cost about 18 per cent less per enclosed square metre than the regional average for a comparable specification, and about 30 per cent more per square metre of roof.
Both figures are true and only one of them is useful. The enclosed area is small because the roof made a smaller enclosure liveable: the kitchen opens onto the covered space and is therefore not sized for a table, and the third bedroom is genuinely small because the outdoor rooms absorb the overflow for eight months of the year.
That is the argument the drawings make, and it is only available in a climate where outdoor space is usable most of the year. Transplanted somewhere colder, the same house is 94 square metres with an expensive canopy. Context is not a garnish here; it is the whole structural logic.
