Materials used in structures
The structure is the frame of the greenhouse, consisting of columns, beams, straps, etc. that support the roof, wind, rain, snow, devices that are installed and overload trellising plants, etc.
They should be kept to a minimum shading and freedom of internal movement. Greenhouse structures must meet the following conditions:
- They should be light and strong.
- Economical and easy care materials.
- Susceptible of being extended.
- Fill the surface optimally.
- Adaptable and modifiable to cover materials.
The greenhouse structure is the constructive element that more time is devoted to be studied in terms of their robustness and economy concerned, to decide whether certain type of greenhouse choose.
The most widely materials used for building greenhouses structures depending on its use are:
- In Pillars, supports and reinforcements: : wood ,galvanized steel, iron and aluminium.
- In straps and beams: galvanized steel, iron and aluminum.
- Arches: galvanized steel or aluminium.
- In foundation supports or foundation bases: concrete.
- In securing the cover: galvanized wire or profiles galvanized steel or aluminum, depending on the type of greenhouses.
- Canals: galvanized steel or aluminum.
- Crop wire: galvanized steel or aluminum and galvanized wire.
It is difficult to find a structure type that uses only one kind of material since it is common to use different materials.
Materials used on the cover:
The most important properties that define a cover are the transmission of solar radiation, transparency to infrared or thermal radiation and heat transfer of the materials they are made of.
Covers are usually made of the following materials:
- Plastic Films: polyethylene copolímeto ethylene vinyl acetate and polyvinyl chloride plastics and multilayer
- Rigid plastics: of methyl polymethacrylate, polycarbonate and polyester.
- Glass: glass patterned glass.