1. Greenhouse Structures and Systems ERT 352

2. What is a greenhouse? A greenhouse is an area designed to grow plants.
It is a controlled environment which allow optimum growth.
When several of these buildings are joined together they are often referred to as a greenhouse range.
A greenhouse at home is usually attached to the house or the garage.

3. Location
There are several factors to be considered in establishing a greenhouse range.
A. Room for expansion
1. Land larger then immediate needs should be acquired.
2.Area should be added to this figure to accommodate service buildings, storage, and access drivers.

4. B. Topography
1. The building site should be as level as possible to reduce the cost of grading.
2. The site should be also well drained. Due to the vast amount of water in the green house it is always advisable to provide a drainage system. Try to select a site with deep, well drained loam, or sandy loam soil.

5. 3. You should select a site with a natural wind break such as a tree line or a hill.
C. Land use Prediction
1. Local zoning and tax laws are subject to change brought on by development pressures. Such changes have brought about the termination of many greenhouse business.

6. D. Climate E. Accessibility
1. The greenhouse site should be selected with specific crops in mind.
E. Accessibility
1. A site should be selected which has easily accessible shipping routes.
2. Select a site that isn’t long distance.
3. Site location is often the deciding factor in the type of fuel used.

7. Types of Greenhouses Even Span Uneven Span Lean-to Quonset Gothic Arch
Curvilinear
Dome Shaped

9. lean to
even-span
uneven-span
ridge-and-furrow

10. Single Span Greenhouse
Note glazing materials. Double poly roof, poly carbonate endwalls.

11. 1. EVEN SPAN Greenhouse with two roof slopes of equal pitch and width
Benefits:
Excellent light, ventilation, and temp control
Disadvantages:
Wasted heat air in the gables

12. EVEN SPAN

13. Even span gutter connected house.

14. 2. GOTHIC ARCH Side walls are a short base wall of a solid material
POINTED ARCH ROOF
TRUSSES HAVE BEEN ELIMINATED
Not as popular today
Can have sidewalls
Side walls are a short base wall of a solid material
often cinderblocks

15. GOTHIC ARCH

16. 3. QUONSET
A greenhouse with a semicircular arch that starts at ground level or on top of a sidewall
(Half moon shape)
Benefits:
Less Expensive to construct
Few shadows
Disadvantage:
Cannot handle as much wind and snow

17. 3. QUONSET

18. QUONSET

19. QUONSET WITH TOP VENT

20. 4. RIDGE AND FURROW
Several greenhouses connected along the length of the eaves
Benefits:
Large interior areas
Reduced heat loss
Less expensive construction
Disadvantages:
More difficult to control pest and temperature
Difficult snow removal

21. RIDGE AND FURROW

22. RIDGE AND FURROW

23. RIDGE AND FURROW

24. RIDGE AND FURROW

25. RIDGE AND FURROW

26. Gutter connected house with automatic plant grader
Gutter connected house with automatic plant grader. Klassic Beauties, Kerry's Bromeliad Nursery, Inc., Florida City, Florida

27. 1. GLASS ADVANTAGES: DISADVANTAGES: Excellent Light Transmission
Available
DISADVANTAGES:
Breakable
High heat loss
Most Expensive

28. 2. FLEXIBLE PLASTIC FILMS
EXAMPLES:
PVC- POLYVINYL CHLORIDE
PVF- POLYVINYL FLOURIDE FILM
POLYETHYLENE- Most Common
ADVANTAGES:
Inexpensive
Easy to Install
DISADVANTAGES:
Not as durable

29. 3. RIGID PLASTIC SHEETS EXAMPLES: ADVANTAGES: DISADVANTAGES:
FIBERGLASS
ACRYLIC- PLEXIGLASS
POLYCARBONATE- LEXAN
ADVANTAGES:
Light weight
Most Durable
DISADVANTAGES:
More expensive than flexible plastic

30. Cooling and Ventilation Systems
No Cooling
NATURAL VENTILATION
FAN & SHUTTER COOLING
FAN & SHUTTER COOLING with SHADE CLOTH
Evaporative Cooling
Fan & Pad (Evaporative Cooling)

31. 1. NO COOLING
1. Inside temperature of greenhouse can exceed 140 degrees F.
2. Plants will die within a short period of time.
                                                                 

32. NATURAL VENTILATION

33. NATURAL VENTILATION

34. FAN & SHUTTER COOLING

35. FAN & SHUTTER COOLING

36. FAN & SHUTTER COOLING with SHADE CLOTH

37. Evaporative Cooling

38. EVAPORATIVE COOLING (Fan & Pad)

39. EVAPORATIVE COOLING (Fan & Pad)
Water Tank
With pump

40. D. IRRIGATION Drip irrigation Mist nozzles Fertilizer injectors
Automatic Controls
Solenoid valves

41. DRIP IRRIGATION (tubes)

42. MISTER (FOGGER)

43. FERTILIZER INJECTORS
SLOWLY ADD FERTILIZERS TO IRRIGATION WATER, AT A SET RATE

44. IRRIGATION CONTROLS
Solenoid Valves
Help control
flow rate

45. Greenhouse Structural Components
Bottom Chord

46. Greenhouse Structural Components
Struts and Chords
Struts are under compression and chords are under tension stresses.

47. Greenhouse Structural Components
A truss is made up of the side posts, rafter, struts, and chords.
TRUSS

48. Greenhouse Structural Components
Ridge

49. Greenhouse Structural Components
Purlin

50. Greenhouse Structural Components
Ridge Vent

51. Ridge-and-Furrow Greenhouses
High Profile
Low Profile
The low profile greenhouse is also known as the venlo greenhouse. Cost differences between the two are very close and often negligible. Low profile greenhouses were originally designed to reduce the amount of surface area exposed to the cold and thus reducing heating costs.
Why would you build a high profile greenhouse?

52. Other structural components
rafter
eave
side post
Mention sash bar
sill
curtain wall

54. Wooden framing.

58. Sawtooth Construction