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Greenhouse Construction - Lecture Notes | AGH 443, Study notes of Gardening and Horticulture

Missouri State University (MSU)Gardening and Horticulture
Prof. Clydette M. Alsup-Egbers

Material Type: Notes; Professor: Alsup-Egbers; Class: Greenhouse Management; Subject: Horticulture (AGH); University: Missouri State University; Term: Unknown 1989;

Typology: Study notes

Pre 2010

Uploaded on 02/24/2010

koofers-user-wny
koofers-user-wny 🇺🇸

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Greenhouse Construction
Other Terminology
Glasshouse
Greenhouse Range
Headhouse
I. Planning Phase Comes First
A. Building and Operating a Greenhouse Requires Information and
Planning
B. Construction Bids Vary Greatly
C. Sources of Information
D. Location
1. Location Is the First Consideration
2. Purchase Twice the Initial Land Needed
3. Add Area for Service Buildings, Storage, Access Drives, Parking
Lot, Holding Ponds
E. Topography
1. Hills Are a Concern when Moving Materials
2. Maximum Automation Possible when Greenhouses and Service
Buildings on Same Level
3. Site Should Be Well-Drained
4. Avoid Frost Pockets
5. Natural Windbreaks Advisable
F. Labor Supply
1. Assess Present and Future Labor Needs
2. Assess Labor Supply in Area
3. Labor among Major Problems in Horticulture Industry
G. Accessibility
1. Accessibility Most Important in Retail
2. Niche Business May Have More Flexibility
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Greenhouse Construction

Other Terminology Glasshouse Greenhouse Range Headhouse I. Planning Phase Comes First A. Building and Operating a Greenhouse Requires Information and Planning B. Construction Bids Vary Greatly C. Sources of Information D. Location

  1. Location Is the First Consideration
  2. Purchase Twice the Initial Land Needed
  3. Add Area for Service Buildings, Storage, Access Drives, Parking Lot, Holding Ponds E. Topography
  4. Hills Are a Concern when Moving Materials
  5. Maximum Automation Possible when Greenhouses and Service Buildings on Same Level
  6. Site Should Be Well-Drained
  7. Avoid Frost Pockets
  8. Natural Windbreaks Advisable F. Labor Supply
  9. Assess Present and Future Labor Needs
  10. Assess Labor Supply in Area
  11. Labor among Major Problems in Horticulture Industry G. Accessibility
  12. Accessibility Most Important in Retail
  13. Niche Business May Have More Flexibility
  1. Select Site with Easily Accessible Shipping Routes (Good Roads)
  2. Site Location Often Determines Type and Cost of Fuel Used at Greenhouse H. Water
  3. Quality and Quantity Are Critical
  4. Test Before Purchasing Site and Test Often I. Land Use Laws
  5. Local Zoning and Business Specifications Should Be Considered
  6. Some Local Governments Classify Greenhouses as Ag Biz
  7. Some Governments Deny Expansion Permits to Floral Producers
  8. State or Federal Regulations May Apply
  9. Neighbors J. Orientation
  10. Greenhouse Structure Casts Shadows
  11. Magnitude of Shadows Depends on Angle of Sun, Season of Year II. Greenhouse Styles A. Quonset B. Even Span (A-Frame) C. Gutter-Connect (Ridge-and-Furrow) D. Retractable Roof E. Lean-To
  1. Life Expectancy
  2. Heat Retention
  3. Resistance to Ultraviolet Degradation
  4. Thermal Contraction
  5. Flammability
  6. Flexibility
  7. More than One Type of Glazing May Be Used
  8. Roof, Corrugated Polycarbonate for High Light Transmission
  9. End Walls in Double-Layered Acrylic for Heat Retention B. Types of Glazing
  10. Glass
  11. First Glazing Used in Greenhouses
  12. Is Still the Premium Material
  13. Most Expensive Glazing due to Cost of Glass and Added Structure to Support Weight
  14. Breakage, especially from Hail, Major Disadvantage
  15. Tempered Glass is Strong
  16. Life Transmission High—Up to 90%
  17. Life Expectancy—Long, One of Longest-Lasting Glazings
  18. Heat Retention—Low, Usually Lowest
  19. Thermal Contraction—Low, Almost No Thermal Expansion or Contraction
  20. Flammability—Fire Resistant
  21. Flexibility—Rigid and Not Suitable for Quonset Type

Greenhouses, Breaks Easily

  1. Polyethylene Film Plastic
    1. Popular because It Is Inexpensive
    2. Many Types Have Additives or Coatings to Prevent UV Light Damage, Fogging, Water Condensation and Dripping and to Retain Heat Longer
    3. Colored Films Are Being Tested for Enhanced Growth or Reduced Stem Elongation
    4. Relatively Easy to Install, Few Support Members Needed Compared with Other Glazing
    5. Replacement of Plastic May Be Difficult in Areas with Frequent Winds
    6. Take Care when Installing Plastic to Prevent Any Punctures
    7. Light Transmission—High for Single Layers but Low (83 to 87%) for More Commonly Used Double-Layered Poly Systems
    8. Life Expectancy—Up to 5 Years in Some Locations, but Usually only 2 to 3 Years
    9. Heat Retention—Single Layers Have Low Heat Retention; but Double Layered, Inflated System Has Excellent Heat Retention
    10. Thermal Contraction—High
    11. Flammability—Low Compared to Fiberglass
    12. Flexibility—Very Flexible; Can Be Used on Almost Any Style of Greenhouse
    13. Cost—Initially Low but Long-Term Cost May Be High due to Short Life of Plastic, especially in High Light Areas
  2. Polyvinyl Fluoride (PVF) Films
    1. Similar Characteristics as Polyethylene Films but Last up to 10 Years and More Resistant to Abrasion and Weather Extremes
  1. Thermal Contraction—Moderate
  2. Flammability—Very High; Burns Fast and Hot
  3. Flexibility—Wind and Hail Resistant, Suitable for Any Greenhouse Style; Highly Impact Resistant
  4. Cost—Moderate
  5. Acrylic
  6. Available in Single or Double Layers (Twin Wall) with 2 Layers Separated by Small Air Spaces
  7. Dead Air Space between Sheets Serves as Insulation
  8. Light Transmission—High, 83 to 90%
  9. Life Expectancy—Long, 25+ Years, if Properly Manufactured and Installed
  10. UV Light and Wind Resistant, but Scratches and Cracks Easily and Becomes Brittle with Age a. Initially Has 8 Times the Impact Strength of Glass
  11. Heat Retention—High with Double-Layered Styles—a 50 to 60% Reduction in Heating Fuel Compared with Glass
  12. Thermal Contraction—High Potential for Expansion/Contraction
  13. Flammability—High
  14. Flexibility—Easy to Fabricate and Install, Few Support Members Needed
  15. Cost—Expensive
  16. Polycarbonate
  17. Available in Single (Corrugated) or Double Layers (Twin Wall)
  1. Double-Layered Types Provide Added Stability and Heat Retention
  2. Panels Lighter and Larger than Glass, Reducing Construction Costs
  3. Single Layer, Corrugated Form Has Become Popular because It Combines Long Life with Flexibility of Fiberglass
  4. Light Transmission—High, 83 to 90%
  5. Life Expectancy—Long, 20+ Years, if Properly Manufactured and Installed
  6. Heat Retention—High with Double-Walled Styles
  7. Thermal Contraction/Expansion—High Potential
  8. Flammability—Low compared to Fiberglass
  9. Flexibility—Easy to Fabricate and Install, Few Support Members Needed
  10. Cost—Expensive but Reduced Fuel Costs of Double-Layered Types Allow Quick Repayment in Cool Climates V. Greenhouse Floors
  11. Dirt
  12. Pebble/Gravel
  13. Concrete
  14. Flood Floor VI. Beds
  15. Beds Minimize Height of Tall Crops
  16. Without Bottoms
  • Watertight to Allow Periodic Flooding with Fertilizer Solution
  1. Space for Hanging Basket Crops a. Often Grown in Air Space above Benches of Pot Crops b. Allows Firm to Use ~ 100% of Floor Space for Production c. Some Facilities Restrict Hanging Baskets to Space above Aisles d. Others Place Baskets over Benches
  2. Containers Grown on Floor a. Pave Floor with Porous Asphalt or Concrete with Gravel Bed Underneath b. Grow Pot Plants Directly on the Floor c. Porous Concrete 4” Thick Will Withstand Weight of Light Vehicles d. Costs $1.30 to $2 ft2 for Materials and Labor e. Efficient Use of Space—Up to 90% of Greenhouse Space Used f. Disadvantage VII. Costs of Greenhouse Construction
  3. $12.25 - $14/sq. ft. Polyethylene
  4. $14.75 - $17.50/sq. ft. Glass a. (see handout)
  5. Does not include Prices of Land, Grading, Service Buildings, Access Drives, Parking Areas
  6. ‘Future’ Costs to Consider a. Replacement of Glazing b. Maintenance of Glazing

c. Fuel Savings for More Efficient Glazing d. Profit from Higher-Quality Crops