What is a greenhouse structure?

Greenhouse- structure covered with a transparent

material, which allows sufficient sunlight to enter for the purpose of growing and maintaining plants

Greenhouse range- two or more greenhouses located

together

The basic function of a greenhouse is to provide a protective environment for

crop production while allowing natural light transmission.

What are the common greenhouse designs?

1. Lean-to Greenhouse shares a wall with a building and relies on the building structure to provide some support for the greenhouse roof.

What are the common greenhouse designs?

2. Even-span Greenhouse

What are the common greenhouse designs?

3. Uneven-span Greenhouse

What are the common greenhouse designs?

4. Ridge-and-furrow Greenhouse

What are the common greenhouse designs?

5. Quonset Greenhouse

What are the common greenhouse designs?

6. Gothic Arch

Bell Ringer #2Tuesday, August 14

What are the 6 common greenhouse structure styles?

Attached GreenhousesConnected to a building (ie. flower shop, garden center,

etc.) – not always a lean-to design

Advantages: Less construction material needed. Can be utilized to heat homes in winter, cool in summer

through heat and humidity exchange.

Disadvantages: Existing building can shade the greenhouse, limiting light

needed for plants. Ventilation and temperature are difficult to control.

Freestanding Greenhouse Separate from other buildings

Advantages: Maximum sunlight available for plants.Allow regulation of many different types of plant

environments.

Disadvantages: More land space needed for building to prevent

shading from other greenhouses or buildings.Require more heat at night due to exposed surfaces.

The greenhouse framework supports the greenhouse covering material.

Ridge

Ventilator

Purlin

Sidewall

Anchor Support Post

Truss

What considerations need to be addressed for greenhouseframeworks?

The framework should be strong, yet allow the maximum amount of light to reach the plants.

It is best if the framework requires little maintenance.

In northern latitudes it is important that the framework be strong enough to withstand heavy snow loads.

What to consider forframeworks?

Aluminum and aluminum/steel combination are long lasting and low maintenance.

Other materials: wood, galvanized steel, and angle iron.

Advantages & Disadvantages of Framing Materials

• Wood-Very good for hobby greenhouses or small custom designed houses: has a low initial cost but requires large amounts of maintenance and painting.

Advantages & Disadvantages of Framing Materials

Galvanized metal-Most commonly used structural material. Due to a coating on the material, very little maintenance is needed and the frames are strong and long lasting.

The cost is higher initially but is cheaper in the long run. Most greenhouse kits come with galvanized metal frames that are predrilled and ready for assembly.

What are the functions of the headhouse?

The headhouse might be used as a storage area, a potting area, an office, and/or a shipping area.

What Materials Are Used for Greenhouse Glazing?The covering of the greenhouse is referred to

as the glazing

Considerations in choosing a glazing material include durability, light transmission, cost, and affects on heating costs

Eight common types of Greenhouse Glazing Materials

Glass Fiberglass

Soft-plastic* Shade fabric

* Three different types of soft plastic: polyethylene, vinyl, polyvinyl fluoride.

Polycarbonate Structured Sheets

Acrylic Structured Sheets

GlassConsidered to be the best material for crop

productionIt has the highest light transmission

The fact that it is very long lasting can make it less costly than other glazing materials in the long run

FiberglassHas dropped in popularityIt discolors after 7-10 years, is flammable and

provides poor insulation

Flexible Polyethylene SheetsFlexible sheets of polyethylene are stretched

over the greenhouse frameworkIt is not very durable, but is inexpensive

http://www.youtube.com/watch?v=SEA_cXjIkAg&feature=related

Structured SheetsStructured sheets, including polycarbonate,

acrylic, and fiberglass materials have grown in popularitySheets made with double walls offer good

insulation

Polycarbonate Structured SheetsThe most widely used because they have

good light transmission, they resist hail damage, and they are easy to work with

Acrylic Structured SheetsHave high light transmission, but they cost

more than polycarbonate sheets, are prone to hail damage, and are less flexible

Retractable-roof GreenhousesAllow the roof to be opened and closed

Retractable-Roof Greenhouses A grower can open the roof when weather

conditions are favorable to plant growth and close the roof when the crops need protectionWhen open, they provide plants with increased

light levels and fresh airRetractable-roof greenhouses can be used to

prepare outdoor crops for the elements before leaving the greenhouse

Other advantages include reduced disease problems because of better ventilation, reduced irrigation due to rainfall, and more effective temperature control

Retractable Roof Greenhouses Designs allow the roof to be opened and closed.Gives plants protection from weather when neededReduced watering, rainwater can be used

What Are Some Greenhouse Bench Options?The greenhouse bench is the structure that

holds the plants above the ground, as opposed to ground bedsMaterials used for benches include expanded

galvanized steel, aluminum, plastic, and rot resistant wood

Benches are arranged in the greenhouse with aisle space and growing space in mind Common layouts include conventional

arrangements, peninsular arrangements, and movable benches

Tomatoes and lettuce require ground beds.

Raised benches are used in the production of pot crops as well as cut flowers.

What Are Some Greenhouse Bench Options?Rolling benches or a type of movable bench

maximize growing space by limiting space for aislesThe benches are placed on pipes, which allows

them to be easily moved from side to side

Greenhouse Benches Holds the plants above the ground. Materials include:

galvanized steel, aluminum, plastic, and rot resistant wood.

Arranged in greenhouse with aisle space to walkRolling Benches:

movable bench used to maximize growing space by limiting space for aisles

benches are placed on pipes, which allows them to be easily moved from side to side.

Rolling Bench