The document provides guidelines for designing greenhouse structures. It describes loads that the structure needs to support, including dead load from permanent structures, live load from movable objects, and wind and snow loads. It recommends orienting greenhouses east-west and spacing them 10-15 meters apart. Size, height, and spacing recommendations are provided based on factors like ventilation. The structural design should support all necessary loads. Components like the roof, walls, supports, and foundations are described. Advantages include higher yields and year-round production, while limitations include high costs and need for care. Gutter-connected greenhouses are also detailed.

2. Design
The structure has to carry the following loads and is
to be designed accordingly
 a) Dead load: weight of all permanent structures and
equipments
 b) Live load: weights superimposed by use (include
hanging baskets, shelves and persons working on
roof).
 c) Wind load: The structure should be able to
withstand winds of 110 kilometer per hour and at least
50 kg per square meter of wind pressure.
 d) Snow load: These are to be taken as per the
average snowfall of the location

3.  Orientation
Latitude above 40°N -east to west.
Below 40°N -north to south.
Multiple greenhouses -East to West. However, the wind
direction and latitude are also to be considered.
 Wind effects
If the greenhouse is naturally ventilated, the advantage of
natural wind direction has to be taken to the maximum
possible. For fan and pad greenhouse the natural wind
direction should be same as the air blown by fan.
 Size of the greenhouse
Bigger the greenhouse, more will be the temperature
build up due to poor ventilation. The length of
evaporatively cooled greenhouse should not be more than
60m.

4.  Spacing between greenhouses
The spacing between naturally ventilated green house
should be 10 to 15 m so that the exhaust from one
greenhouse should not enter the adjacent greenhouse.
 Height of greenhouse
The maximum height can be up to 5m for 50m x 50m
green house and this can be reduced as per the reduced
size of the green house. Higher is the greenhouse more is
the wind load for structure and glazing.
 Structural design
The greenhouses are to be designed for necessary safety,
serviceability, general structural integrity and suitability.
The structure should be able to take all the necessary
dead, live, wind and snow loads. The foundation,
columns and trusses are to be designed accordingly.

5. Components of greenhouse
 Roof: transparent cover of a green house.
 Gable: transparent wall of a green house
 Cladding material: transparent material mounted on
the walls and roof of a green house.
Rigid cladding material Ex. Glass
Flexible cladding material Ex. Plastic film
 Gutter: collects and drains rain water and snow which
is place at an elevated level between two spans.
 Column: vertical structure member carrying the green
house structure
 Purlin: a member who connects cladding supporting
bars to the columns

6. Cont……
 Ridge: highest horizontal section in top of the roof
 Girder: horizontal structure member, connecting
columns on gutter height
 Arches: Member supporting covering materials
 Foundation pipe: Connection between the structure
and ground
 Span width: Center to center distance of the gutters in
multispan houses
 Green house length: dimension of the green house
in the direction of gable
 Green house width: dimension of the green house in
the direction of the gutter

7. Advantages of greenhouses :
 Higher yield
 Reliability of crop increases under greenhouse
cultivation.
 Ideally suited for vegetables and flower crops.
 Year round production of floricultural crops.
 Off-season production of vegetable and fruit
crops.
 Efficient utilisation of chemicals, pesticides to
control pest and diseases.

8. Cont……
 Water requirement of crops very limited and
easy to control.
 Hardening of tissue cultured plants
 Production of quality produce free of
blemishes.
 Modern techniques of Hydroponic (Soil less
culture), Aeroponics and Nutrient film
techniques are possible only under
greenhouse cultivation.

9. Limitations of green house
 High initial cost
 Need constant care with maintenance of
structure and conditions
 Need special care with pollination of crop
 If pest enter into the green house control is
difficult

10. Gutter-Connected Greenhouse
 A gutter-connected greenhouse is a series of gable or gothic arches
connected together at the gutter-level. Post lines support the gutters
and drains are provided inside to carry the water away.
Advantages of gutter-connected greenhouses
include:
Less land is needed
About 30 percent more growing area can be placed on the same
amount of land area as free-standing greenhouses.
Utilities
Utilities are easier to install. Electrical service, water supply and
computer systems are centralized making installation and maintenance
less expensive.
Heating costs
As the glazing area to floor area ratio is less, heating costs are as much
as 25 percent less than an equivalent floor area of free-standing houses.
Heating can be simplified with one or two boilers instead of multiple
heaters.

11. Cont….
Cooling costs
With natural ventilation, open roof designs, fans are not
needed and the temperature is more uniform throughout
the growing area.
Greater labor efficiency
Carts and conveyors can be easily adapted as everything is
under one roof. Movable bench/tray systems also adapt
more readily. Labor is easier to control.
Greater plant density
Most gutter-connected greenhouses are built with a 14- or
16-foot gutter height to allow for the energy truss and to
provide space for one or more levels of hanging plants.

12. THANK YOU