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   A-Frame
 

The retractable A frame greenhouse comes in two basic models; the conventional A frame and the low cost A frame Rafter greenhouse. The conventional A-Frame truss is designed for heavy snow and wind loads and has spans that match up with most standard house widths. The lower cost A-Frame Rafter house is designed for covering large areas in the sunbelt where crops need to be protected from cold, wind, heat and rain, but there is less snow than in colder climates.

Conventional A-Frame Greenhouse A-Frame Rafter Greenhouse
  • 5/12 roof pitch
  • Truss designs for up to 70lb/ sq ft snowload and 140MPH (225KPH) windload
  • House widths of 24ft, 30ft, 31-6ft, 36ft,41-6ft
  • 10ft (3.2m)- 20ft ( 6m) gutter height
  • One motor can close 45,000sq ft (4,000 sq m) in 2.5 minutes
  • 3/12 roof pitch
  • Truss designs for up to 15lb/ sq ft (73kg/sq m) snowload and 110MPH (177 KPH) windload
  • 48ft ( 14.63m) between gutters
  • 13 ft, 14.5 ft (4.5m) gutter height
  • One motor can close 45,000sq ft ( 4,000) sq m in 2.5 minutes
The retractable roof system and covering is designed with windstand high loads.
The structure and roof system can be designed for heavy snowloads and have withstood 7 hurricanes
without losing one roof covering or structure. (Standing on the roof is not recommended)
  Above picture was taken after Hurricane Wilma.  The 6 year old A frame roof was closed during the 200kph ( 130mph) winds and sustained no damage.  The adjacent steel covered packing house was severely damaged.
Two choices of roof coverings, clear for cold and mild climates, and white for hot and mild climates. 
The RC02 woven and coating roof coverings generally have a useful life of 8 to 12 years.
RC02 is a roof covering that has been field tested for 14 years, has higher light transmission, and greater fatigue resistance.

 
Features
       High light transmission (Approximately 80%)
       UV stabilized woven and coated polyethylene
       Blocks approximately 90% of UV radiation and absorbs approximately 60% of long wave radiation
       ASTM E84 results: Flame-spread 20, Smoke development 45
       High tear and impact resistance
       Usable life is typically 7 to 12 years on retractable A-Frame roofs
       Includes limited worldwide 4 year pro-rated warrantee.*
       A-Frame retractable roof greenhouse can be used in virtually all climates for all crops since they can be designed to protect crops from extreme levels of snow, rain, wind, hail, heat and insects while still allowing crops to benefit from the natural outdoor environment when conditions permit. The range of environmental control possibilities goes far beyond the retractable roof. Complete flexibility can be achieved through the addition of roll up sidewalls and retractable curtains that can be used for:
       Light and temperature control
       Photoperiod control
       Insect exclusion
       Additional heat retention
 
The A-Frame greenhouse with roll up walls
 
The retractable roof can automatically be fully closed, fully retracted or partially closed to create the best possible environment for the crop based on the outside weather conditions.
When a computer controls the roof, crops can be automatically:


protected from excessive cold, rain, wind and snow by closing the roof.

exposed to normal levels of UV, PAR, and infra-red radiation, by retracting the roof completely.

 protected from excessive UV and infra-red radiation by closing the roof 85%.
 

The walls that have motorized roll up curtains can be automatically:

opened:
 
for ventilation when it is raining
 
to expose crops to wind when it is beneficial
 
to improve ventilation when the roof or curtain system is closed 85% for heat reduction
closed:
 
to protect plants from cold/ rain or snow
 
to protect plants from excessive wind
 
to help prevent drift when overhead irrigating or spraying
If crops require protection from insects, stationary insect net can be installed on the outside of the roll up curtain openings.
 
Expanding the range of environmental control using additional stationary or retractable curtains

Clear woven poly
White woven poly
Blackout- heat retention
Insect net
       

Winter production is energy efficient since the clear woven curtain can be closed as an energy curtain to create two layers of poly. Curtain could be closed on extreme cold days to reduce energy costs without significantly reducing light levels. The clear curtain can also be used in the summer to provide cooling by intercepting the infra-red radiation while still allowing plants to receive high light levels.

Winter production is energy efficient since the white woven curtain can be closed at night as an energy curtain to create two layers of poly. The white curtain can also be used in the summer for additional shade and to provide cooling by intercepting the infra-red radiation

 The blackout system is beneficial for providing photoperiod control to crops like chrysanthemums, poinsettias, and tree seedlings and for additional heat retention at night Insect pressures can be reduced or eliminated using stationary or retractable insect net. Plants still receive exposure to UV and infra red radiation which helps plants develop their natural color, shape as well as disease and insect resistance. Light levels can be maximized since the insect net can be retracted when insect pressures are minimal or when the roof is closed.
 
 
Structure Features
       Standard house widths 24' (7.3m), 30' (9.14m) , 31'-6" (9.6m) , 36' (10.98m), 41'-6" 12.65m) , 42' (12.8m)
       Gutter heights up to 24ft (7.1m)
       Designed to handle snow loads of up to 70 lbs./sq. ft. (342 kilo./sq.m.)
       Designed to withstand up to 120 mph winds (193 kph)
       Designed to meet required crop loads
       Fire retardant roof coverings are available for retail applications

 

     

Polycarbonate or metal roof coverings can be used to cover potting area or dry goods area Trusses under the gutter can create wider opening for main roadways inside the greenhouse. Roofs can be moved using a drill in the event of a power outage 
 
Product Brochures
   Retractable A-Frame Greenhouses
   A-Frame "Rafter Style" Greenhouse
   Los Invernaderos A-Frame Retràctiles
   Invernaderos Retráctiles A-Frame Modelo Rafter
 
Support Information
   Retractable Roof Control Strategy
   Guidelines for New Retractable Roof Greenhouse Projects
 

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