ABSTRACT
Greenhouses are framed or inflated structures covered with a transparent or translucent material in which crops are grown under partially or fully controlled environment conditions. Greenhouse structures as well as other methods of controlled environments have been developed to create favourable micro-climate in favour of better crop growth and production all the year round. Cultivation of crops under protected structures with climate controlled environment is usually intended to create off-season opportunities for the production of high valued vegetables, ornamentals, fruits etc. Greenhouse structures differ a lot from simple and very cheap structures to high-tech multispan structures. An uneven span greenhouse is a type of protected structure with one roof slope longer than the other or/ the roof is not equal in width or pitch, thus called uneven span type greenhouse and the steeper angle of structure faces the South. Cladding materials are the most important constituent of protected structure as they have direct influence on micro-climate inside the structures.
