How to Make Sure Your Greenhouse Can Withstand Heavy Snow

Posted by Brian Sparks|December 18, 2017

To provide additional support in double poly-covered greenhouses, two-by-fours can be placed under weight bearing bow and purlin connections; however, snow removal may still be required.

Strong winds, gray skies, and cold, snowy days have arrived in many areas of the country. As a greenhouse grower and operator, are you prepared to remove heavy, wet snow that accumulates in greenhouse gutter-connects or blankets poly-covered greenhouses? If you do not have a plan, you may find yourself scrambling to save your greenhouse from collapsing.

In a report posted on the Michigan State University Extension website, Greenhouse and Floriculture Outreach Specialist W. Garrett Owen reminds growers that the moisture content of snow can vary dramatically. Dry snow typically occurs over areas far away from large bodies of water, at very low temperatures. Snow is wet after it picks up moisture from nearby lakes, or when the temperatures hover around 32°F. Wet snows can weigh four times as much as dry snows, causing a considerable amount of weight bearing down on every square foot of greenhouse roof surface.

Snow load of a greenhouse is based on expected ground accumulation, greenhouse roof slope, whether the structure is a gutter-connected or free-standing greenhouse, and if the greenhouse is heated or unheated during the time of snowfall.

For specific tips on snow melting methods based on the type of greenhouse you may have, check out the complete report.