Air space in lid

[Johnny253]

I am building some home made hives. Can anyone tell me why hives have an airspace in the lid? I'm considering using flat timber which would be much simpler to make. Since hives have a mat sitting on the frames, I can't see why an airspace above this is necessary, other than being a place to feed the bees when required.

If it's for ventilation, then surely ventilation holes would be better. If it's for insulation, then surely a thicker lid would be better.

I'm interested to hear your thoughts.

[ShaneJ]

I think I understand what you are asking. You don't have to have space above. For example a telescopic lid leaves no space above but a migratory lid does. In my opinion having space above allows the bees more room to chase SHB.

[Michael Bush]

The inner covers from Brushy Mt. are flat on the side that goes down.  The migratory covers are flat.  You'll have a minimum (1/4") beespace with a flat cover.   3/8" would be better.  As the propolis builds up under the ends of the top bars that space shrinks over time.

[Johnny253]

Thanks for the advice guys. I reckon I'll cut the groove for the frames to sit in a fraction deep, to leave a bit of extra space on top and go with a flat cover with some holes for ventilation.

[west end apiary]

IN australia they use migratory lids, for the ventilation and for the ability to place them closely on pallets. I use the space in the lid for an idea of when the flow starts. WHen they are really cranking along they fill the lid space and I know that I have to start looking at extracting. I am pretty new to beekeeping but think I will stay with the migratory lids because it can get hot in queensland and have seen bearding which I am trying to avoid due to links with swarming.