Overwintering in Polyurethane Hives

Thursday 12 January 2023

In Atlantic Canada, honey bees (and beekeepers!) endure long winters. Many of us wrap and winterize standard Langstroth hive bodies with different insulating materials to help colonies survive the cold winter months. However, what if it was possible to house our bees using a more insulating material all the time? Beekeepers currently have additional options and a choice of technologically advanced materials for housing colonies. One such novel material is polyurethane honey bee hives.

Overwintering in polyurethane hives

Polyurethane hives are an alternative to traditional, wooden Langstroth bee hives. Similar to Langstroth hives, polyurethane hives use standard size, removable frames in vertically stacking bodies. They are advantageous because of their lightweight, insulating walls. High insulation value offers potential to support honey bee colonies kept in cold climates. During the winter, colonies are primarily focused on regulating cluster temperature at around 34-35°C. This is an energy demanding task, at a time during which foraging for food resources is not possible. Supporting colonies with insulation can reduce energy needs, much like insulating a home reduces heating costs. This can extend food stores, which is a great relief in the spring when beekeepers are anxiously awaiting the first nectar bearing flowers.

Researchers in Maryland recently performed a study to compare the overwintering capacity of polyurethane hives with standard, soft-wood Langstroth hives (Alburaki and Corona 2022). Eighteen double deep, 10-frame hives, evenly divided between polyurethane and wooden, were standardized for bees and food stores before the winter period from December to March. Sensors were placed within each hive to monitor temperature and humidity, not of the honey bee cluster, but of the surrounding hive cavity.  Polyurethane hives maintained significantly higher internal temperatures than wooden Langstroth hives, as well as less drastic temperature oscillation between day and night. Polyurethane hives had an average temperature of approximately 10.20°C, compared to unwrapped, wooden hives at 9.73°C. During the monitoring period, outdoor apiary temperatures ranged from -10 to 20°C, with an average of 0°C.  

Another challenge for honey bees in the winter is maintaining optimal hive humidity. Polyurethane hives maintained an average humidity more preferable to honey bees at 52.05%, compared to 63.50% average humidity within wooden hives. Polyurethane hives have vents in the top and bottom that provide valuable airflow. Comparatively, the wooden hives revealed a wider range of humidity between night and day, demonstrating wood’s propensity to absorb moisture during cold, nighttime temperatures and then release moisture as the day warms. Such oscillation of internal conditions may cause honey bees to use more energy to maintain an optimal environment, thereby consuming more food. 

It is important to recognize that the Langstroth hives in this study were not winterized. In preparation of long, cold winters it is typical for Atlantic beekeepers to insulate hives to some capacity, whether it is a foam board between the inner and outer cover or bubble-wrap around the outside hive body. Though this study does not provide insight as to the advantage of polyurethane hives compared to wrapped, insulated Langstroth hives, it does present a modern option for overwintering colonies. Polyurethane hives may be an alternative technique for northern beekeeping, in which external wrapping during the winter is not necessary. 

Ben Cornect’s nuc yard. Polyurethane nucs are organized as six per pallet. ©ATTTA

At the Atlantic Bee Tour this summer in Nova Scotia, we saw an example of one beekeeper who is already taking advantage of the high insulating properties of polyurethane bee hives. Ben Cornect showed beekeepers his nuc yard, where he has begun successful experimentation with overwintering nucs in polyurethane hives! As innovation in beekeeping continues, it is worthwhile to consider your own operation and how new technologies might serve your beekeeping goals. 


Mohamed Alburaki & Miguel Corona (2022) Polyurethane honey bee hives provide better winter insulation than wooden hives, Journal of Apicultural Research, 61:2, 190-196, DOI: 10.1080/00218839.2021.1999578

Connecting with ATTTA Specialists

If you’d like to connect with ATTTA specialists or learn more about our program, you can: