Saunas tied down to survive a cyclone

Tie-downs are the first drawing, not the last

Cyclone season runs roughly November to May in the south-west Indian Ocean, and a well-built cabin is anchored against uplift rather than relying on its own weight. Galvanised straps and threaded rod into concrete pads, sized and signed by an engineer where the exposure warrants it.

We draw the anchorage before we draw the cabin, because it decides the floor frame, the deck fixings and often where the cabin can go at all.

Humidity that never lets up

Nothing dries on its own here. Every enclosed room gets mechanical extract with a long run-on timer, ducted out. Cabins sit on a ventilated void rather than flat on a deck. Timber is thermo-treated, charred or oiled teak — untreated softwood has a short, unhappy life on this island.

Vapour barriers are continuous, on the warm side, with every penetration sealed. A gap in a barrier here traps moisture in the wall, which is worse than none at all.

Teak, basalt and what comes from where

Teak is imported and it is worth it: dimensionally stable, naturally oily and beautiful in this light. Basalt is local — the island is volcanic — and it is the right material for plinths, plunge tubs and thresholds.

Coral stone is local and limited, and we use it sparingly for benches and detail rather than by the square metre.

In short

• Cyclone tie-downs drawn first, engineer-signed where exposure warrants
• Ventilated void under every cabin and run-on extract in every enclosed room
• A4 stainless throughout — humidity here is continuous, not seasonal
• Imported teak, local basalt, coral stone used sparingly