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Flat Roof X-Frame A-Frame 6 Steps to Create the Optimal Retractable Roof Production System based on your Climate and Crop Step 1: Choose the house model which best addresses your climate and crop needs Step 2: Choose the colour of the roof covering Step 3: Decide if a rain canopy should be added to allow for ventilation through the roof when it is raining Step 4: Decide if additional climate control is required Step 5: Decide on the design of the perimeter walls Step 6: Automate the control of the retractable roof and walls Cravo Models & Options • Page 3

Step 1. Choose the house model which best addresses your climate and crop needs Climate and Crop Requirements Uncoated Flat Roof Coated Flat Roof X-Frame Rafter Loading capabilities Wind speed house must resist when roof and walls are closed: kph (mph) 0 - 110 ( 0 - 70 ) 140 -177 ( 87-110 ) 0 - 200 ( 0 -125 ) Snow and hail load when roof is closed: kg/m² ( lb/ft2 ) 0 - 25 ( 0 - 5 ) 25 - 50 ( 5 - 10 ) 0 - 240 ( 0 - 50 ) Crop load Must support the load of a crop like tomatoes or hanging flower baskets Crop requirements Plants must be kept 99% dry Suitable for young plant production...

CROSS SECTION OF HOUSE MODELS (PRODUCT COMPARiSONS}

Arrow indicates Roof closing direction

Roof Coverings Step 2: Choose the colour of the roof covering The retractable reinforced polyethylene roof coverings are available in clear and white. The best colour for your project depends on whether you are growing in a cold or hot climate. Clear: best when daytime temperatures in the winter are White: best when daytime temperatures in the winter too cold to retract the roof (typically at latitude 30 -50 ) are optimal and when summer temperatures are extreme (year round at latitude 0o-30o and summer production at latitude 30o-40o) Flat roof with clear roof covering Flat roof with white...

Step 3: Decide if a rain canopy should be added to allow for ventilation through the roof when it is raining if you would like to be able to ventilate during rain for humidity control, then it is recommended to install a rain canopy in the following conditions: • if the house is smaller than 1 hectare ( 2 acres) and none of the perimeter walls are covered with roll up curtains • if the house is larger than 1.5 ha (3 acres) and rainfall can occur for long periods of time

Choose whether to add one or more of the following: • A misting system Decide if additional climate control • a stationary or retractable insect net is required • An interior retractable cooling, shading and heat retention curtain system if production occurs where temperatures are +30oC (86oF) and humidity levels will be below 55% Add a misting system if you are growing high light crops like berries and tomatoes TEMPERATURE REDUCTION Temperature (dry-bulb) If growing crops between latitudes 30o-50o where winters are cold and summers are hot Use a clear retractable roof covering and a...

Internal curtain orientation The optimal orientation of the interior curtain system depends on the direction of the gutters If the gutters are at least 15 degrees off North/South, the interior curtains should travel from truss to truss in the opposite direction from roof If the gutters are oriented perfectly North/South, the interior curtains should travel across the house from gutter to gutter Cravo Models & Options • Page 9 3

Perimeter Walls Step 5: Decide on the design of the perimeter walls The optimal design of the perimeter walls will depend on if: • Winter temperatures are too cold • Humidity levels are high or low during the summer • Crops need to be protected from insects • Crops will benefit from exposure to wind • Wind will be beneficial to dry soil out after a rain • The region is susceptible to hurricanes or cyclones • It is desirable to prevent rodents from entering the production area If production is located where winter temperatures are warm and humidity is high: cover walls with stationary insect...

if crops would benefit from wind, if wind would help dry out the soil after a rain or if the house could be hit by a hurricane or cyclone, cover the perimeter walls with motorized roll up curtains if crops need to be protected from insects when the roll-up curtains are open, then install insect net over the roll-up curtain openings if ground is uneven or if rodents should be prevented from entering through the walls, then install a knee wall below the roll up curtain Roll up curtains are powered by gear motors which slide on a guide shaft and are balanced using a counterweight.

Step 6: Automate the control of the retractable roof and walls Over the last 10 years, Cravo has developed special sensors and computer control algorithms to ensure that you can take full advantage of the benefits of both the natural outdoor conditions and a protective greenhouse and shadehouse environment. The control system includes: • A weather station that measures surface temperature, wind speed, wind direction, rain and barometric pressure • Indoor sensors that measure air temperature, humidity, soil wetness and soil temperature • An interface to connect to a desktop PC for ease of...