Steam rooms and hammams for Zanzibar houses and Dar villas

Waterproofing that suits coral and lime

We line the room with wedi building boards — we have sold wedi officially since 2015 — sealed at every joint and corner, over a floor membrane and a screed that falls at least 1:50 to the drain. The ceiling is pitched or domed so condensate runs down the walls instead of onto the bench.

Where the room sits against an existing coral-rag or lime-plastered wall, the board and tape stand clear of it with their own continuous seal. Those old walls survive because they breathe; steam driven into them travels and reappears as damp elsewhere in the house.

Extract on a humidistat, ducted outside

After a session the room needs several air changes through a fan ducted to the outside air, and on the coast that fan runs on a humidistat rather than a timer. A timer cannot tell a dry afternoon from a monsoon evening; a humidistat keeps the fan on until the room is actually dry.

Extract that ends in a ceiling void is not ventilation at all. It moves the water into the roof, which in a Stone Town house is the worst possible place for it.

Rainwater, borehole or mains

Many island houses run on harvested rainwater or a borehole; Dar villas often mix city water with a tank. Rain is soft and kind to a generator; island boreholes can scale one within months. We test the supply that will feed the generator and choose an auto-flush model or a softener accordingly.

Indigo mosaic or coral stone

Zanzibar's colours — indigo, lime white and dark hardwood — suit a steam room better than any imported look. A mosaic-lined room with a coral-stone bench costs more than porcelain tiles, and the quote shows both side by side.

A domed ceiling in the Zanzibari manner looks right and sheds condensate well, but it needs a larger generator than a flat room of the same floor area; the quote shows the difference.

Send the room dimensions and a photo of the space; you will get an itemised price within one business day.

In short

• wedi boards sealed at every joint, kept clear of breathing coral walls
• Fan ducted to open air on a humidistat, not into the roof
• Rainwater, borehole or mains tested before the generator is chosen
• Indigo mosaic and coral benches priced honestly against porcelain