Structural Parts Greenhouse Types Even Span: Self-supporting commercial greenhouse and is the most common type of greenhouse Ridge-and-furrow: Two or.

Structural Parts

Greenhouse Types

Even Span: Self-supporting commercial greenhouse and is the most common type of greenhouse

Ridge-and-furrow: Two or more even-span greenhouses connected together at the eaves

Contiguous: Two or more even-span greenhouses with inner walls separating each greenhouse

Greenhouse Types

Quonset: Upside down half circle made of laminated wood or bent pipe. Can also have raised walls

Gothic: Slightly pointed greenhouse covered with corrugated fiberglass. Provides greater load bearing for accumulation of snow

Lean-to: Seldom used commercially and found attached to the south wall of a south supporting structure

• When building a greenhouse frame consider:– The strength and weight of the materials– The amount of shade cast by the frame

• The frame is composed of:– Perlins– Sash bars– Side posts

Greenhouse Frame

• Aluminum– Alloy: Aluminum combined with other

materials to increase strength and flexibility with rust and rot resistance

• Plastic pipe• Wood or wood

combination

Framing Materials

Covering Materials

Cover Type Advantage Disadvantage

Glass• Best for transmitting

light to plants• Initially expensive• Easily broken

Plastic, flexible

• Provides insulation• Inexpensive

• Pass less light to plants• Considered temporary• Often need replacement

after one or two years

Plastic, rigid

• Last longer that flexible plastic

• Less chance of breaking• Withstand weather

better than flexible plastic

• Will eventually yellow or weaken

• Pass less light than glass

• Unit heaters• Hot water heat• Root zone

heaters• Steam heat• Infra-red heating• Solar heating

Heating Systems

• Evaporative cooling– Pad absorbs water and

exhaust fans pull air through the pad and greenhouse

• Natural cooling– Replaces air inside

greenhouse with outside air

• Fog cooling– Fog nozzles installed in

greenhouse emit a fog

Cooling Systems

• Raised benches: raised off the floor, generally 24-36 inches

• Ground beds: constructed directly on the floor and filled with media

• Movable benches: also called rolling benches, raised bench built to roll sideways

• Ebb and flow bench: raised bench approximately 3-6 inches deep and capable of holding water

Benches and Beds

• Parallel: Benches run the length of the greenhouse and have several aisles

• Peninsular: One major aisle in the center or the greenhouse with short perpendicular aisles

Common Bench Arrangements