GREENHOUSE Flashcards
(FLOOR AREA REQ) Benches should be up to _____ wide if they are to be access from both sides, and should not exceed ______ if they are accessible only from one side.
1.8 m , 0.9 m
(FLOOR AREA REQ) An air circulation space of approximately _______ shall be allowed between the sidewalls and the benches.
160 mm
(FLOOR AREA REQ) For fixed benches, the usable space should be _________ of the floor area while ________ for rolling benches.
66%-75% , 90%
(WALKWAYS) If the walkway will be used only as a place to stand while servicing the benches, a minimum of ________ aisle shall be used for determinate crops and a minimum of _______ aisle for indeterminate crops.
0.3 m , 0.8 m
(WALKWAYS) The width of the walks shall be adjusted if machinery will be used. Larger greenhouse often have __________ secondary aisle and __________ primary aisle.
0.6 m - 0.9 m , 1.2 m -1.8 m
(WALKWAYS) If a worker is in a wheelchair, __________ wide aisle shall be used and ramps shall be provided for easy access.
1.2 m
(FLOOR LENGTH AND WIDTH) When figuring the length of a plastic structure, an extra _________ shall be allowed to fasten the plastic properly.
0.6 m
(FLOOR LENGTH AND WIDTH) The length of the greenhouse should not exceed __________.
50 m
(FLOOR LENGTH AND WIDTH) For gutter connected greenhouses, the total width should not exceed __________ for well distribution of air.
50 m
(BUILDING HEIGHT) The eave height for a gable roof greenhouse shall be atleast _________ with a minimum gable height of _________.
1.7 m , 2.4 m
(WORKING HEIGHT) Gutter heights of __________ are recommended for multi span houses to allow machines to move freely.
2.8 m - 3.0 m
(WORKING HEIGHT) The height of the house in the walk areas shall not be less than ________.
2.0 m
(WORKING HEIGHT) For tall crops, _________ shall be the minimum height at the eaves and __________ as minimum desirable height.
2 m , 2.1 m
(FOUNDATION) For permanent greenhouses, all foundations shall be of durable material and shall extend to a minimum depth of _________.
0.45 m
(WALLS) Height of side posts and columns should be _________.
0.3 m - 3 m
(WALLS) For greenhouses with wooden structural members, a _________ high reinforced concrete wall at the bottom shall be provided for support.
0.4 m
(FRAMES) Framing shall adequately support the covering and any equipment and/or hanging baskets suspended from the framing. It shall be able to carry trellising loads up to ___________.
25 kg/m²
(FRAMES) Framing shall be able to withstand maximum wind gusts of __________.
250 km/hr
(FRAMING MATERIALS - WOOD) Rafters should be placed __________ from center to center, depending on the strength requirements.
0.6 m - 1.2 m
(FRAMING MATERIALS - WOOD) Greenhouses over ________ wide shall require a reinforced truss construction.
15.25 m
(FRAMING MATERIALS - WOOD) Purlins should be connected by a cross tie. __________ spacing should be used depending on the size of the greenhouse.
1 m - 2.5 m
(COVERING) It should be durable as well as economical and should withstand heavy loads like wind gusts of ____________.
150 kph
(COVERING MATERIALS) Polyethylene sheet roofing shall have a minimum thickness of __________.
130 úm
(ROOF PITCH) Roof pitch for a glass greenhouse should be _________ to prevent inside condensation from dripping on plants.
51%
(ROOF PITCH) Plastic covered greenhouses require a steeper pitch of ____________ to prevent drip.
58% - 70%
(GUTTER) For gutter connected greenhouses a __________ slope shall be provided for drainage.
2%
(ACCESS) Large doors in the end of the greenhouse should be provided. If walking tractors are to be used, ________ wide standard doors shall be provided. A minimum of _________ wide side doors shall be provided.
1.2 m , 0.8 m
(FLOOR AND WALKWAYS) A concrete, gravel or stone walkway __________ wide should be built for easy access to the plants.
0.6 m - 0.9 m
(BENCHES) Benches should be of height and width suitable to an averaged size worker, benches shall not exceed ________ high when against the wall.
0.9 m
(BENCHES) For temporary benches for growing and bedding plants, benches as wide as __________ and only ____________ high should be used.
1.5 m - 1.8 m , 0.45 m - 0.6 m
(BENCHES) When shade plants are to grow under the benches, bench heights as high as ________ should be used.
1.2 m
(ARTIFICIAL LIGHTING) Artificial lighting should be provided for the production of photo-period sensitive plants and for the workers, _________ lux should be provided.
200
(IRRIGATION AND DRAINAGE) A general rule of thumb to follow in irrigating greenhouse crops is to apply _________ more water than the container will hold to facilitate leaching at each irrigation and reduce the potential for the accumulation of soluble salts.
10% - 15%
(IRRIGATION AND DRAINAGE) The recommended drainage rate is ___________ of the water dose given to the plant. The drained water should be contained in a storage tank.
30% - 50%
(IRRIGATION AND DRAINAGE) Soil beds and benches are leveled with a slight slope of __________ to drain the water dripping from the media containers.
0.8% - 1%
(NATURAL VENTILATING SYSTEM) Large vent openings provide the most ventilation, the total vent area should be ___________ of the floor area.
15% - 25%
(NATURAL VENTILATING SYSTEM) Top hinged ridge vents should form a _______ angle with roof when fully opened.
60⁰
(MECHANICAL VENTILATING SYSTEM) A maximum ventilation rate of __________ air exchange per minute is recommended for most greenhouses.
3/4 - 1
(MECHANICAL VENTILATING SYSTEM) Ventilation fans should deliver the required ventilation capacity at _________ static pressure when all guards and louvers are in place unless specific design requirements require air delivery at higher static pressures.
0.03 kPa
(MECHANICAL VENTILATING SYSTEM) Fans should be spaced not more than ________ apart for uniform ventilation.
7.5 m
(MECHANICAL VENTILATING SYSTEM) If the fans must be located on the windward side, increase the design ventilation capacity at least _________.
10%
(MECHANICAL VENTILATING SYSTEM) A clearance between the fan discharge and any obstruction of at least ________ the fan diameter should be maintained. Fans may be mounted in the roof if obstructions interfere with other mountings.
1.5 times
(MECHANICAL VENTILATING SYSTEM) Intake louver area should be at least ______ times the area of the fans.
1.25
(MECHANICAL VENTILATING SYSTEM) Manufactured guards should be used or install a woven wire mesh screen of at least ______ (gage 16) wire and_______ openings, for placement within 100 mm of moving parts.
1.5 mm , 13 mm
(MECHANICAL VENTILATING SYSTEM) Guards more than 100 mm
from moving parts may be made with woven wire mesh of _______ (gage 12) wire, and _______ openings.
2.7 mm , 50 mm
(PAD AND FAN COOLING) The pad to fan distance should be _______.
30 m - 50 m
(PAD AND FAN COOLING) The pad is normally run continuously along the side or end of the house opposite the ventilation fans. Vertical pad height should not exceed _______ nor less than be ______ for uniform water flow.
2.5 m , 0.5 m
(PAD AND FAN COOLING) Pad location is not as important when the greenhouse is sheltered from prevailing winds by another building or greenhouse located within ________.
7.5 m
(PAD AND FAN COOLING) Keep fans from exhausting directly into pads on an adjacent greenhouse, unless they are separated by at least ________.
15 m
(SHADING) Overhangs should be sized to fit the particular design requirements of the space. The length of the overhang should be _________ of the glazing height, and the height of separation between window and overhang should be ________ of the window height.
1/3 -1/2 , 1/4
(INSTRUMENTATION AND CONTROLS) The shade should be made of a material having a low thermal conductivity and high reflectivity such as white painted wood. Wood should have a minimum thickness of _______.
13 mm
