Phil, I like the idea of the pvc pipe. Totally cool and simple!!! You da Man!!!! However my bees like to beard in summer and just hang out on the entrance. My concern is how the bees will adjust, what about washboarding? May be my concerns are in vain I just don?t know?? Thoughts anyone???
Also ventilation in my very humid environment is a concern in early summer as I like my honey in the 16-17 percent moisture range. If my entrance is not full open, I get 18% honey which is OK but I prefer the lower moisture content which makes for thick honey, a favorite of mine. Just personal preference. I am guessing upper and lower openings might accomplish more air flow resulting in lower moisture in my honey, if I were to try the pvc pipe method of beetle control. Or an upper vent, which is already on most of my hives, then add PVC pipe on bottom or top which is another factor.
Top or bottom entrance is another question which is addressed on M. Bush web pages as well as others.
Blessings
Van