It prevents cluster heat from condensing on the cold inner cover, which can moisten the cluster during a vulnerable time of year.
Homemade hive wrap/ 1/2 foam board : r/Beekeeping
Insulation for National Beehives : 7 Steps - Instructables
Beeswax Coated - Beehive is beeswax coated which made bee hive waterproof and more durable. Food grade plastic foundations dipped in 100% beeswax so
10 Frame Beehive Starter Kit, Beeswax Coated Bee Hives Includes 1 Deep Bee Boxes and 1 Bee Hive Super with Beehive Frames and Beeswax Foundation
Honey Paw polystyrene beehives
DIY Foam Beehive Winter Shelters
This 10 Frame assembled kit comes complete with the essentials you need (minus the bees) to get you started right away. If you are catching swarms or making splits, this is a perfect way to start them off. Later, you can either reunite colonies or top with additional stories. Comes with all the components needed to start a colony quickly. Please check the document here to learn more about your options when purchasing this kit.
Unassembled Essentials Beehive Kit - 10 Frame | Betterbee
Why Would You Put Bees in a Polystyrene Hive?
How to make follower boards for a Langstroth hive - Honey Bee Suite
Custom-fitting your winter boxes to your wintering bees.
Queen Bees Rearing Box Double Layer Beekeeping 10 Frames Foam Hives Box, Bees Mating Box DIY Beekeeping Hives for Reserve Tools