Admittedly, I haven't built this one yet. However I did design it. This is a telescoping top cover with the addition of 1.5 inches of rigid foam insulation. Its total R-Value is about R-8.75. Normal top covers have an insulation value of less than 1.
Pine (at least 3 3/4" wide, and 81 1/8" long)
Ext Plywood 3/4" - 22 1/2" by 18 7/8"
Plywood 1/4" - 22 1/4" by 17 7/8"
Like all project I am going to assume you are using our favourite barn board. So get that table saw out, and rip a strip off 3 3/4"
Discard the larger piece. Now create the recess which holds the insulation.
Now cut that strip into our required parts. You will need:
- (2) 18 7/8"
- (2) 21 1/2
That finished, it is time to assemble the basic frame using whatever fasteners you choose (nails, staples, screws, glue).
Next place the piece of 1/4" plywood (22 1/4" by 17 7/8") in the recessed area. Although it is not necessary to fasten it, I would recommend it.
Place the rigid insulation in the recess. Once again, not necessary to fasten it, but using some adhesive could be beneficial.
Fasten the plywood top, and you are away to the races. You may wish to wrap the hive in aluminum flashing for weather protection. That is a different tutorial however.