post- by Gautam Shah
Built form designing begins with a neatly defined geometric shape, but it evolves into a very complex form. A complex form becomes an architectural adventure to gain new spaces, experiences and uses. The basic form was modulated, followed by its vocabulary and treatment and ornamentation. In few years time the original entity is so morphed that the new entity becomes the defacto form or solution.
There are several ways this is done:
1. Modulate the surface from a plane to singly and doubly a curved entity.
2. Introduce curving lines in parallel or perpendicular to gravity planes or askew planes.
3. The basic unitary geometric shape is recast into a formation of several volumetrically modulated entities.
4. Taper or enlarge the form in upward or downward directions.
5. Trim or Shape the edges and corners.
6. Transgress the form inward and outward, with voids and solids.
Building forms are transgressed to the exterior for many different purposes. The prime purpose is to enlarge the interior space, to open out the omni present sense of enclosure, to bring in the lightness of the exterior, to stretch the internal and external surface area to enhance the built mass, to add a textural entity over the surface, to add thresholds (in-between) spaces and to sideways view, aeration or sunlight facilities.
Corner projecting oriel
■ ORIEL: Oriel windows are a form of polygonal bay windows. Oriel windows, have a larger perimeter then a normal flat window, and so allow wider view of the outside. Oriel windows increase the floor space without increasing the footprint (extent) of the building. Oriel windows are usually placed on the upper floors of the building, but siting on ground floors is not common. The windows are projected bays, supported off the base-wall by columns, piers, corbels or brackets.
Such windows have of many forms: start from the floor level, seat level or mid body level, the head-side of the projected gap terminates at lower, at human head level or reach to the ceiling level. Some oriels are partly or wholly glazed. Oriel windows like latticed forms are found in Indian Zarokha and in mid East or Arab architecture as Mashrabiya. In both the cases the lattice reduces the glare and provides privacy. Zarokha is more commonly made of stone work, and Mashrabiya have carved wood latticework and often stained glass. Oriels are also found extremely dark streets. Oriel windows were also placed over gateways or entrances to manor houses and public buildings.
■ BAY WINDOWS: A bay window is an exterior projection of room space, forming a bay of square or polygonal shape. The round shaped (segmental) windows are called bow-windows. Bay windows became popular with Victorian architecture (1870’s). A typical bay window consists of three windows, the middle unit is parallel to the house and adjoining two units are set at 30 to 45 degree angles. Bay windows are created: to increase the illumination, provide a wider view of the outside and enlarge the interior space. The bay windows are used on sunny sides in colder climates, over sections facing road side, garden and other natural scape.
There are three basic types of bay windows. In full bay window the opening stretches from floor to ceiling level to create a nook in a room. In half or part bay window the window starts at seat or nominal sill level and reaches head height level or full ceiling level. In the third version the bay is more of a flower box projecting out. The nook created by full bay window is well illuminated and has better view of outside so it is used as study area, breakfast space, solarium, hobby area, etc. For these purposes the inner ledge of the bay window is used as built-in seat.
The building act of 1707 in London and other towns of England did not allow projections on a road side, to prevent spread of fire along the wall. This was changed in 1894 so that windows were not required to be flush with the exterior wall. During the Victorian and Edwardian period houses began to have bay windows.
Ground Floor Bay window
■ BOW WINDOWS: A bow window, is a curved or polygonal bay window. Unlike the bay window, there is no middle window unit, parallel to the room. Instead, several small width window units (fixed and shuttered) are joined to form a bow shape. Bow windows first appeared in the 18 C in England and in the Federal th period in the USA. Bow windows are also called compass window and radial bay windows.
■ MASHRABIYA: Mashrabiya is a projected window on second or higher floor in mainly in urban setting, but rarely in rural areas. Mashrabiya was used in houses and palaces although sometimes in public buildings such as hospitals, inns, schools and government buildings. It is commonly placed on the street side, but occasionally on the internal courtyard ‘sahn’ side. Mashrabiya windows are presumed to have formed during 12th C in Baghdad. Iraq and Egypt are two countries where many examples survive. They are more common in Eastern (Mashriq) parts of the Arab world then the western (Maghrib) parts. Basra is often called the city with Mashrabiya. It was introduced in France from its colonial sources, and called moucharabieh.
Mashrabiyas are enclosed with carved wood latticework, composed of the lathe turned wooden sections called bobbins, in complex patterns. Smaller lattice openings in the lower section obscure vision from outside and reduce the air draft, whereas larger openings in the upper parts allow better air draft and illumination. Lattice design differs from region to region. Mid part of the Mashrabiya is provided with sliding or a side-hung shutter for a clear opening. Mashrabiyas are also lined with stained glass to form an enclosed balcony, and an independent space attached to a room. Mashrabiya in farm houses and for out of the town buildings are more open, with reduced amounts of lattice work and without the lining of glass.
Egyptian Mashrabiya projects out at a slightly raised level providing for a Dakkah (a Dakkah is a masonry platform attached to the front part of a house, covered with a rug, it is used for informal talk and tea in Arab rural areas, an arrangement similar to Ota or Otla in a traditional Indian house) or in front of the window similar to the Indian Zarokha.
Mashrabiya adds space to rooms on the upper floor without increasing the foot print area of the building, but these have also been used for correcting the shape of upper floor front room. Mashrabiya allows air from three sides to enter, even if the draught outside was parallel to the house facade. Mashrabiya also provides shade for the ground floor windows.
The word Mashrabiya has varied origins. Mashrabiya denotes drinking or absorbing. The name perhaps has derived from a wood lattice enclosed shelf located near a window to cool the pots of drinking water. The shelf evolved until it became part of the room with a full enclosure. Mashrabiya also has originated from verb Ashrafa =to overlook, ignore or to observe.
■ SHANASHIL: Shanashil (shanshool or rushan) is a porch, verandah or gallery like features covered with fine wood lattice work. It is found in old Iraqi houses of Baghdad. Shanashil is also a net or wood screen-covered verandah or porch over looking a street or garden.