Unfortunately, sheep’s wool in the form of insulation mats is usually treated with moth repellents. Please do not use this for the Diffusion lid! It is also best to buy untreated sheep’s wool directly from the shepherd or farm. Hemp insulation wool is also permeable and can be used as an alternative. The insulation properties are, however, slightly worse.The upper side of the insulation should be regularly checked for moisture. If it is wet, the underside must also be checked. If this is also wet, the insulation should be replaced by a wooden fibreboard (thickness 4-6cm). It allows less diffusion. This reduces the risk of water condensation on the top of the insulation. The consequence is an increased humidity in the beehive and therefore the danger of condensation in the beehive.
Standings as of 9/20/2017:
The sheep’s wool in the Dandant Blatt hive is slightly clammy on the top, inside and on the bottom it is very dry. This place is going as planned.
In the Sachs Schiffer hive, the sheep’s wool was completely wet this morning. I removed it immediately. The surface of the lid is almost 1/5 of the surface of the lid of a Dadant hive, therefore there is a much higher load per cm². The moisture that accumulates is not absorbed quickly enough by the air on the top surface, and the water condenses. I have replaced the wool here with hemp insulation wool, increased the layer thickness and increased the distance to the rain protection. These measures may not yet be sufficient. The next step would be to switch to wooden fibreboards if necessary.
In the middle of November both beehives are equipped with sensors, and then we get an insight into the effects on the hive climate in practice.