First, we provide an overhang with our homes, which should prevent the majority of rain from entering the front of the nesting blocks. Second, we use white oak to make the blocks themselves, which unlike a material like plastic, can breathe and does not trap moisture. In tests where we left the wood fully submerged in water for over a day, water only managed to enter the end grain of the wood a couple millimetres, and dried quickly, and practically did not penetrate the face grain at all. While some dirt may collect on or between the blocks, they will generally remain well insulated from the weather once the mother bees complete them and seals the front.