"One of the biggest benefits for growers who live in areas prone to storms is that they can retract hectares of roofs in less than 6 minutes allowing them to react only when the storm will hit their location." Speaking is Richard Vollebregt with Cravo. Two weeks ago the company showed in a video how their retractable greenhouse underwent a tropical storm.
Top photos: Cravo greenhouse two months after Hurricane Irma came through with gusts reaching 180 kph (110 mph).The roofs and walls were retracted before the hurricane. Conventional poly houses (lower two photos) were destroyed.
Open or close
The video of the retractable roof system was released some weeks ago and gained a lot of attention since heavy weather is a major issue for growers. "The reinforced polyethylene roof coverings can't blow off since they are suspended below stainless steel wires."
Hectares can be retracted in less than 6 minutes
"Growers have a choice to leave the roof closed during the storm to protect the crop or retract the structure and walls to protect the house in the event that the winds are forecast to exceed the design load of the structure," explained Richard Vollebregt with Cravo.
"One of the biggest benefits for those growers who live in areas prone to these storms is that they can retract hectares of roofs in less than 6 minutes allowing them to react only when the storm will hit their location." This means that growers do not have to decide days ahead of a hurricane arrival whether to cut the poly off their roofs when a major storm is forecast.
If the winds are forecast to be greater than the design load, hectares of roof and walls can be automatically retracted in minutes to protect the structure and coverings. In the event of a power failure after the storm, the motors can be manually powered using an Allen key turned by hand or a drill that is powered by a battery or a generator.
For more information
Cravo Equipment Ltd
30 White Swan Road,
Brantford Ontario, Canada N3T 5L4
Phone: +(1) 519 759 8226 x 215
Mobile: +(1) 519 732 8054