Sunday, May 25, 2014

AWNINGS



Awnings are sun and snow shading devices over openings like doors, windows and shop fronts. Awnings are also used for forming the entrance spaces. Awnings are made of flexible fabric or sheet material that can be rolled or folded when not required. Hard awnings are made from stiffer sheet materials and have rigid and permanent support system. Awnings with column or bracket supports are canopies. In India hard awnings are also called Chhajjas.


In ancient Egyptian and Syrian civilizations, awnings of woven mats were used for shading the market stalls. Roman poet Lucretius (50BC) describes ‘Linen-awning, stretched, over mighty theatres, gives forth at times, a cracking roar, when much 'tis beaten about, betwixt the poles and crossbeams. A Velarium covered the Colosseum in Rome. It provided both shade and slight protection from rain, although the main use of the Velarium was to create ventilation up-draft, creating circulation and a cool breeze. Velarium effectively shaded one-third of the arena and seating and another third was shaded by the high surrounding walls. From the word Velarium (from velare to cover) it is believed that sailors, with their background in sail-making and rigging were employed to build, maintain and operate the structure.



Ancient texts describe a form of Mandapa (or Mantapa)of temporary nature with four corner supports of wood or bamboo. Chandani (or chandarava) tied by four stretched strings has been described in Jain literature. Mughal miniature paintings show Shamiana or Pandal is a tent shelter for daytime and evening entertainment. Shamiana was used as temporary resting place by royals when on the move. The external fabrics were multicoloured with exquisite designs. The four corners are supported with wooden poles.






Awnings, became very popular during the early 1900's when shop windows or shop fronts became possible with the economic availability of clear large sized glass. However, in Asian bazars awnings have been in use for many centuries, for summer sun shading and rain shading during monsoons.



Awnings are used to extend the buildings. Early awnings had hard wood or bamboo as front cross bar, whereas the support edge was secured by grommets (eyelets) and hooks, or tied by laces to the head rod or support bar. The front end was supported either by inclined spears or metal posts.



A canopy is a fixed awning like structure, supported on all sides. Canopies are used to extend the shaded space near an opening system. Canopies are used to cover the passageways or car drive bays. Canopies are demountable and fold-able but not necessarily retractable or collapsible like an awning. Dutch type or canopy awnings are similar to a perambulator hood, with an umbrella like folding frames.



Structure of an awning is very light. It has a flexible cover and a very light weight support frame that can be retracted or folded. The cover is made with a canvas or similar heavy duty fabric of cotton, polyester or polypropylene fibres. Layered composites of fabrics and polymer sheets, and coated fabrics are also used. Modern awnings are of single colour or with stripes of two or more colours. Awnings often have a festoon, valance or Toran like borders at its front edge. Awnings on shops, restaurants and hotels have their name and logo on the roof face and on the front edge.


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