Bee hive with thermal insulation for hanging in the tree
The Gruibert hive is a double-walled wooden bee hive insulated with hemp insulation wool for hanging in a tree. Some characteristics of these hive correspond to those of natural tree cavities. It represents a compromise between such a natural habitat and usual bee hives. The hive is equipped with the following characteristics:
- Thermal insulation comparable to that in a tree cavity inhabited by bees, the insulation of the sides and the lid corresponds to that of over 40cm solid wood.
- Entrance hole with Ø 4cm and a length of 19,5cm
- Bees have a volume of 37 litres available
- Operation with top beams
- Geometry based on tree cavities inhabited by bees higher than wide. Use of “Kuntzsch high” frames possible (dimensions: upper part 274/25/8, lower part: 250/25/8, side part 330/25/8)
- Honeycombs can be accessed from above and below
- Hanging in the tree
- Bottom screen board
- The hive can be reconstructed with simple means and without special previous knowledge
Probably the most important thing is the high thermal insulation. Not only because of the thermal insulation itself, but also because of the effect on the amount of condensation in the beehive.
The building instruction for this hive is intended as a motivation to offer your bees an attractive home. Maybe you can think of some improvements, I am looking forward to your ideas and variations! Take the screwdrivers and give your bees a proper insulation!
Material list for the build of the bee hive Gruibert
- Just under 24m rough sawn boards with a cross-section of 24mmx180mm.
- Since it inevitably comes to waste, purchase of 7x 4m boards.
- 4m rough sawn battens with 24mmx48mm cross-section
- 50cm squared timber with cross section 8x8cm for the entrance hole and for mounting on the tree
- About 200 wood screws: M4 – 60mm long
20 wood screws: M4 – 40mm length (only for screwing the battens to the bottom flap)
- Roofing felt 90cm x 85cm
- 200cm wooden strip with cross-section 1,0cm x 2,0cm
- 3mm wire rope with plastic sheath + 4 wire rope clamps
- 2 screws: M8 with 12cm length, wide screw head
- 2 screws: M10 with 20cm length for screwing in the tree
- 2 small angles, side length 2-3cm
- hemp insulation wool
- linseed oil varnish
Required tools for building the hive
- cordless screwdriver
- 3mm drill bit for pre-drilling incl. lowering for the countersunk heads of the screws
- Forstner drill 40mm diameter for the entrance hole
- circular hand saw or circular table saw
- diagonal cutter for the wire rope
- wrench for the wire rope clamps
Dimensions and system plan of the bee hive
How to build the bee hive Gruibert
- Screw boards D to C and form a frame (Figure 1), 3 times in total
- Screw the floor boards (2xD and 2xA) onto a frame from one side to the other (Figure 2 & 3).
- Screw the boards A and B together and insert them into the floor. The boards B should be flush with the floor boards, they rest with their entire surface. The boards A only rest with 9mm on the floor boards, 15mm are free. There must be a clear width between the two inserted boards A of 26.5cm, this dimension has priority over the dimensions mentioned above (Figure 4).
Mark the entrance hole on the outside and inside (on boards A and C): The entrance hole should be a few centimetres above the lower edge of the prey. Now drill through the outer and inner boards with the 4cm-Forstner drill. For the tunnel between the boards use a 14.7cm long squared lumber (8x8cm). Move it into the correct position and screw it together. Then drill through the existing holes from the outside and inside with the Forstner drill bit so that the holes meet as exactly as possible in the middle (Figure 5 & 6). I had installed the entrance hole only at a later time, therefore straw is already to be seen on the picture (please select hemp insulation wool!). However, the entrance hole should be made at an early stage before the insulation material is filled.
Fit the second frame (Figure 7) and insert boards A and B loosely. Move to the correct position with the help of boards loosely placed on top: Again, the boards B should be flush, the boards A are only 9mm covered by the loosely placed board (Figure 8). The uncovered surface later becomes the bearing surface of the honeycomb frames. Mark the boards in the correct position (Figure 9), take them out again and screw them together as marked (Figure 10). Then insert it again and screw it to the frame.
Now the chambers are filled with insulating material or stuffed with light pressure. The ceiling boards can now be screwed from one side to the other (Figure 11).
The 3rd frame, which will form the roof, is screwed to the boards E on one side. The boards E protrude 3cm on each side of the frame after mounting (Figure 12).
The 4 boards F are placed on the other side of the 3rd frame, starting flush on one side. The 4th board must be shortened lengthwise so that it is flush with the frame. The frame is now filled with straw and the boards are screwed together (Figure 13).
Saw off two 26.3cm sections from the 1x2cm strip and screw them together on the underside (where the entrance hole is) as shown in Figure 14 (and on the opposite side). Screw a frame together from the same strip, with the external dimensions 26.3cm x 38.8cm. Nail or tack a grid on one side. A low-cost variant is roller grilles with a mesh width of 0.5 cm. However, the holes are still too large and can be crossed by bees. To prevent this, a second grille can be applied at a different angle (see Fig. 15).
Screw the 2 boards G for the bottom flap as shown (Figure 16) using the wooden slat (cross-section 24x48mm). Attach a frame around the bottom flap from the wooden slat with locking option (Figure 17). There should be a gap of 2-3mm between the frame and the bottom flap.
Finish top beam (Figure 19) or use “Kuntzsch high” frames. Cut the cloth to fit the upper beams (Figure 20).
The roofing felt is attached to the lid of the hive by turning it over at the edge and stapled or nailed from below.
All outside of the hive should be painted with linseed oil varnish.
The hive is placed on the back of a squared timber (8x8cm, 30cm long, Figure 21) screwed to the tree. On the front side it is attached to the branches above it with wire ropes. In order to provide the wire ropes with the correct length, the hive is first hung up with tension belts. The 2x M8 screws for the wire suspension are first only screwed so far that the screw head still has approx. 3cm distance to the wood. First, the tensioning straps are fastened here. The wire ropes are guided around stable branches (diameter > 10cm) above and fastened with wire rope clamps. With the other end, a loop is also placed around the M8 screw. When the wire rope clamps are bolted, the tensioning straps can be removed. Now the M8 screws can be screwed together as far as they will go (Figure 23) The support on the tree is screwed together with 2x M10 screws of 20cm length. To prevent the hive from slipping horizontally, it should be fixed with 2 small angles (Figure 21).