Reduce Worry by Winterizing Your Greenhouse
Time spent now means money saved and a better night’s sleep.
Winterizing your greenhouse now will save you money and possibly major headaches later on. With fuel costs being high this year, it is even more crucial to check the greenhouse for leaks, inspect heating systems and perform maintenance on equipment. Todd Beeler, Engineering Manager at Stuppy Greenhouse, says the most important tip is to keep up with regular maintenance all through the year. “Anything that moves is eventually going to need cleaning, lubricating or adjusting,” he says. “Keeping up with that throughout the year is best practice, but there are some extra chores in the fall.”
Beeler and Michael Kovalycsik, Marketing and Regional Sales Manager at Stuppy Greenhouse, provide ten tips to help you get through the winter in good shape — both structurally and financially.
1. Support the structure. In areas where snow and/or strong winds are likely, check and tighten bolts and fasteners in all areas of your frame. In regions where heavy snow is likely, create and keep handy a support system of 2” × 4” posts that can be placed under the bows and trusses within the greenhouse to support the extra weight. “In a severe winter event in an unheated structure, be prepared to cut the poly and let the snow fall through to save the greenhouse,” Kovalycsik says. “Poly is about $400 per greenhouse, while the structure may be $20,000. You hope to never have to do this, but it’s far less costly than losing the greenhouse.”
2. Mind the gaps. If warm air escapes through gaps, money is flying out with it. Check both personnel and garage doors to make sure they close tightly and add weather stripping around all entryways if it isn’t already installed. “Inspect the roof and the entire greenhouse for breaks or tears. Patch holes and make sure lock inserts are secure. Caulk gaps wherever they appear around gaskets, joints or in the foundation,” says Beeler.

Insulating pipes helps to conserve heat through colder months.
3. Inspect and clean all heating systems and controls. The heating system is the most commonly overlooked. Many growers only think about the furnace when it breaks. If you’re thinking about replacing your furnace already, consider doing it now. Make sure a licensed service company inspects and cleans the furnace, heat exchangers and associated air ducts so your system is in good working order.
4. Insulate to conserve heat. If using floor heating, insulation around the side and end walls is a good idea. This can be done at construction with 1” – 2” insulation panels sunk into the ground at 12” – 24” depth and rising to the level of the knee wall. Otherwise, foam insulation can be sprayed on the side and endwalls at a 1” – 2” thickness. “Insulation of the lower walls is especially effective if floor heating is being used,” Kovalycsik says. Make sure heating pipes, water pipes and air ducts are insulated with 1” – 2” foam insulation as well.
5. Inspect inflation kits. Make sure blowers are all operable, and importantly, that the air intake is free and clear. If there is a sag in the inflation hose, water can collect from condensation, which is then blown between the layers of poly, leading to ice buildup. It is a good practice to install a manometer in your polyhouses. This device monitors air pressure to prevent plastic stretching in the summer heat; the recommendation in winter should be 0.45.

Growers can save between 20% – 30% on energy costs when energy curtains are in good operating order.
6. Inspect energy curtains. Make sure your energy curtain controls are in good operating order and curtains slide easily. Repair any tears. Energy curtains can save 20% – 30% on your heating bill, because you’re not heating the upper part of the greenhouse at nights. However, during a larger snow event, there are times when you need to allow heat to flow up to the roof.
7. Inspect and lubricate vent motors. Beeler advises growers to tighten and adjust bolts and fasteners, so racks work together to ensure vents operate smoothly and easily.
8. Clean gutters so water can flow easily, which will reduce ice formation in the gutters.
9. Seal or remove evaporative cooling systems. If you have an evaporative cooling system and are not using the greenhouse, drain irrigation lines and cooling lines in cold-temperature areas. Remove cooling pads and fans in greenhouses that will remain empty or cover them with poly to seal the openings.
10. Have a backup generator in good working condition if – and inevitably when – you lose power. Installing a working alarm system will alert you to any power outage, helping you sleep better at night.
Inspect, clean, maintain, repair – this is the theme of winterizing your greenhouse. Acting now will save money and time, and perhaps help you avoid catastrophic events. Please contact the experts at Stuppy Greenhouse, who are ready to work with you and answer any questions.