Since I am new to bee keeping. I have not experinced the problems that I hear of. I under stand that winter moisture buildup is a large problem on THBs. I have 2 traps out and waiting. Mean wile I am working on 2 hives if I should need them. The hives are completed all except the roofs. I am trying to solve problems before I experiance them. Has anybody ever tried building a double thickness roof. The roof would be built to have one thin layer of wood about 2 inches above the bars. I think this should be between1/8 and1/4 thick and be flat to allow the moisture to be absorbed. Then the upper roof would be sloped to allow for drainage (rain/snow). There would be an air space between these two roofs. This air space could be vented on both ends to allow the air to circulate in the cavaity thus allowing the moisture that is absorbed into bottom side the thin roof to evaperate out the opposite side. This will keep a draft free enviorment for the bees and rid the hive of excess moisture. One bar may have to be modified to allow moisture to rise above the bars. If this makes sense give me your feed back and if you think I am not crazy I may try one. This could keep hive cooler in the summer also.