Stone Town’s architecture is as unique as its history. The town itself is a living monument to the centuries of cultural fusion and trade that shaped the nation.
Doors
Perhaps the most striking and spectacular impression of Stone Town for its first time visitor is the magnificent wooden doors serving as grand entrances to the grand buildings.
The doors have become more or less synonymous with the Swahili culture in East Africa, Lamu and Mombasa (Kenya) and in Zanzibar. Zanzibar has more and more elaborate doors than on the mainland and thus the doors are named ‘Zanzibar doors’. An inventory done in the 1980s reported around 800 doors. Unfortunately has the number decreased, not only due to the diminishing of several houses, but also due to theft following the increased attention from international collectors.
The doors demonstrate unsurpassed technical and artistic craftsmanship. Wealthy traders and house owners appointed skilled carvers brought in from India for the delicate job of arranging the entrance ornament. The oldest doors are often made out of Burma (Indian) teak, shipped all the way from Asia across the Indian Ocean. The shutters are made in one impressive piece and not mended together as is the case on newer doors. The Burma teak no longer exists, so newer doors are made of East African teak. Even this wood has become rare and difficult to find, often demanding a very high price.
In principal there are two types of doors found in Stone Town. The Indian doors, or Gujarati doors, with square shutters and made into smaller sections so that the door can fold together. These doors are to be seen along the busy bazaar streets where the Indian businessmen lived. The second type is called ‘Arab doors’, these doors are often found with an inscription in Arabic – most likely a phrase from the Holy Quraan – on the top frieze, and richly decorated around the frame. The older doors were all square at top. The semi-circular frames were introduced later, but are still referred to as ‘Arab doors’. The custom of putting brass knobs on the shutters comes from India, where the knobs were said to prevent elephants from crushing the doors. Since there have been no violent elephants in Zanzibar the brass knobs were simply but there as a decoration and to show the wealth of its owner.
By looking at the lower part of the side posts a rough estimate can be done of the age of the door. The oldest doors have a symbol resembling of a fish. The fish gradually transformed into a shape of a pineapple and thus if the carving shows a clear and distinct pineapple the doors is of a newer generation. Another symbol that became part of the decoration was the chain-like row at the very outside of the whole door. The chain was said to protect the entrance from evil spirits.
One of the oldest doors in Stone Town can be found at the entrance to the Old Fort. Another one is the well maintained door at the Zanzibar Conservation Centre (former Old Customs house) along the Forodhani seafront (See Landmark Buildings).
Stone Walls
Try to use a modern cell phone inside a traditional Stone Town building. The reception will fail and the call will never get connected. The average thickness of a wall in Stone Town is 40 – 60 cm. The building material used is coral rag and lime mortar, an appropriate technology for a hot and humid climate where heat needs to be kept out and humidity varies over the seasons. When the monsoon swept in over Zanzibar the walls managed to absorb the dampness. The material in the walls could expand. When the hot and dry season entered the walls dried out and the heat was kept at bay.
Due to neglect and poverty many buildings have already collapsed in Stone Town. The sad remains of those crumbled houses show the handsome work of the walls interior. The coral stones and mixed with sand and mortar, holding the construction together.
Floors, ceilings and roofs
Most rooms found in traditional houses in Stone Town are quite narrow and deep. This is because traditionally, floors and ceilings were made with mangrove poles, which only grow a certain length. Only in houses where imported teak could be afforded, and in later constructions where iron beams were introduced, are the rooms wider and more spacious. Lime mortar was also used for the floors and ceilings giving the same flexibility to building as the walls. The height from floor to ceiling was generous and made it possible for the air to circulate and cool off. Initially the houses had flat roof with a crenel around the top. When corrugated iron was introduced to the Island, many houses got an additional pitched roof on top.
Zanzibar louvers and other details
The windows in the Stone Town buildings are also worth some attention. They often stretch from floor and high up the walls, with deep niches protecting the inside room from direct sun-light. The lower part at floor level had separate shutter that could open and helped to increase the ventilation in the rooms – once again an appropriate construction for the humid climate. The special louvers, even named ‘Zanzibar louvers’, at the mid part or upper part of the windows have a vertical stick in the middle making it possible to change the angles of the louvers. This finesse made it possible to open for maximal light and air and then close for privacy and shade.
The Arab houses had in general plane facades with windows giving the inhabitants the possibility to look out but no one from outside could look in. The Arab women were not supposed to be seen in public and hence there are often no outdoor sections of these houses. Still, several houses can be found with the most beautifully decorated verandas. Some of these houses have had their balconies added later or the houses were built by Europeans or non-Arabs. The Zanzibar Conservation Centre (the Old Customs House) is one example of an Arab-mansion that has had its significant veranda some thirty years after its original construction. 
A typical detail at the houses in Zanzibar are the stone benches either outside the house or seen in the first hallway when looking in from the main entrance door. These benches, or sitting arrangements, are called ‘baraza’ in Kiswahili and a symbol for the rich social life in the Swahili culture. The outside baraza benches are often found in the merchant part of Stone Town were business could both discussed and displayed openly. In the Arab houses the baraza benches are find inside. In the more prominent Arab houses there was even a second ‘Zanzibar door’ in the hallway leading to a room where guests could be invited for more private discussions. Black and white marble tiles found on the stairs and entrance to a house is yet another sign of wealth and importance of its owner.
It is estimated that Stone Town today has about 1700 houses; a good number of them are unfortunately in a poor stage and in immediate need of repair. A survey done in 1992 showed that almost 25% of the houses were Government property, about 20% belonged to a religious Trust Commission (Wakf), and nearly 50% were privately owned, leaving about 6% as unknown property.
Stone Town Heritage Society 