Jan 25, 2016

How to prepare your greenhouse, high tunnel for winter storms

Given the recent heavy winter storms throughout many portions of the U.S., here are some tips from Rimol Greenhouse Systems to reduce storm damage to your greenhouse and high tunnel.

5 tips for wind loading

• Close up the all openings, including vents, louvers, and the doors. Whatever outside force is applied to the high tunnel is doubled when allowed inside the building. In essence, the wind entering the structure will attempt to force the walls and roof outwards and upwards.
• Research the typical wind patterns on your property. The building orientation can reduce the friction and pressure on your tunnel when set up correctly. You want your tunnel to provide the least resistance possible.
• For air inflated greenhouses, increase the pressure on the inside to reduce rippling effect of the poly. Double down and make sure any slits or openings are taped with film repair tape.
• Use windbreaks to reduce the wind speed or deflect wind over the greenhouse. Typical windbreaks are conifer trees such as hemlock, spruce, or pine at least 50’ upwind from the greenhouse – far enough that falling limbs will not come into contact with the structure. Wood or plastic fencing can also be used as a buffer.
• If you have a metal chimney, stove pipe, or any exterior ventilation susceptible to high winds, secure them with sheet metal screws.

5 tips for snow loading

• Leave at least 10 to 12 feet between individual greenhouses so that snow can accumulate. This will also prevent sidewalls from being crushed in as pressure builds from added snowfall over the winter.
• If you have a heating system, it should be equipped to maintain a temperature of 60 degrees Fahrenheit to melt snow and ice and preventing excessive build up. Make sure the heat is turned on at least a couple hours before the storm begins.
• Pull energy screens aside to allow heat to get to the glazing and melt snow and ice.
• Make sure you have diagonal bracing to keep the greenhouse from racking from the weight of snow and ice. If you don’t already have this installed, consider retrofitting your structure. It will add years to your investment.
• Keep the following three items on hand:

1. Durable lumber to brace your structure and complete temporary repairs.
2. Brooms to help push snow off of poly structures without damaging the cladding.
3. Backup poly for temporary repairs and to ensure heat is retained to protect crops.