screen size

[applebwoi]

I would like to build a screened bottom board. Will regular aluminum window screen work or do I need to get a particular mesh size?

[Kurt Bower]

Screened bottom boards provide a couple of benefits.
It seems as if it they are good for additional ventilation.
They are also good for letting the varroa mites drop down and out of the brood chamber. You will need to run a #8 mesh in order to keep other insects out but allow the mites to pass through.

Kurt

[Michael Bush]

#8 is standard. Betterbee uses #6. Aluminum window screen will not let the mites fall so freely.