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  • Ventilation

  • General Q&A, Bee chat and only Bee chat please
General Q&A, Bee chat and only Bee chat please
 #11277  by MickBBKA
 22 Jun 2021, 01:32
I wonder what are folks thoughts and experiences with regards to ventilation ?
Winter is one thought for later in the year but I am thinking more of so called Summer.
In recent times I have started to go back to solid floors but with a varroa mesh above and no ventilation on the crown board as my bees most always seal it up. I was once asked why I have no top ventilation, my answer was that I had never seen my bees fanning the entrance....
Do we give ventilation just because we are taught by the BBKA and other rote teaching without any evidence for its use ??
Last year my strongest and most productive colony was one that I had failed to realise I had left the varroa section in place.

Me, I think that open mesh floors need a rethink. What evidence do we have that mite fall is nothing more than just old dead mites who are not able to rejoin the colony and would be dead regardless of the floor. I have taken control of some very very old colonies a few years ago on solid floors and they were immaculate. The comb was black as death but the colonies were amazing......Are we missing something....??
 #11289  by AdamD
 22 Jun 2021, 16:49
There's two aspects to your question Mick, one is to do with ventillation and the other is related to varroa control.
I don't ventillate to top of my hives at any part of the year; the roofs are sealed and there is usually a piece of insulation material present; either in the roof itself or a piece that (annoyingly) falls out and has to be put back each time. The bee escapes do tend to get glued up with propolis - so that tells me that it's what the bees prefer.
For the floor; I use mesh floors and usually have the mite board out although I am not too worried if it is in place and very few seal well in any case; the Thornes correx board is particularly bad and gets blown away if I am not careful. I used reduced entrances too. Over time the mesh floors tend to get propolised although this is more likely with a small square of mesh - as I have in my WBC's for example. A full mesh floor doesn't usually get propolised much.
My expectation is that solid floors in winter would result in more mouldy combs compared to a better-ventillated floor.
As to varroa, I guess that some live varroa will fall down and crawl back if they are on a solid floor; live varroa fall used to be noticeable when icing sugar dusting was the thing - and if vaselene was put on the board, it would catch a few that would otherwise walk off or get nabbed by ants. I don't have mite boards in enough or study them enough to say whether they collect many live mites. (Maybe I should).
 #11291  by Alfred
 22 Jun 2021, 17:44
After some near fatalities and a bit of trial and error over a couple of seasons I've found a setup that works( in my location) which catches extremes of weather but is predominantly damp.

Crownboard with no holes, Insulation slab on 365 days,omf with no tray(ever).
Bees are dry and easily regulate their temperature at all times- and they overwintered strongly.
Who would have guessed -it actually matches the hollow tree cliche too..........
I'm sure it was a ( rare unadulterated)Dave Cushman article that described bees circulating air up, around and back out through the floor as and when they required it.
I don't believe a permanent hole above the cluster is helpful-I think it's a perpetuated myth that's come about due to the use of feeder/clearer boards when solid crownboards are not supplied with the new hive kit they've just bought
 #11318  by AdamD
 25 Jun 2021, 11:47
"I don't believe a permanent hole above the cluster is helpful-I think it's a perpetuated myth that's come about due to the use of feeder/clearer boards when solid crownboards are not supplied with the new hive kit they've just bought".

I have seen beekeepers who leave the porter escape holes open in their crownboards with the usual ventillated roof on top. A bit like leaving the loft hatch at home open in winter.
 #11319  by NigelP
 25 Jun 2021, 12:43
An old Victorian parlour trick when all bees where on solid floors was to take a candle to the entrance when there was a flow on. On one side of the entrance the flame would be sucked inwards on the other-side it was blown outwards. Meaning on solid floors bees were directionally manipulating the air flow inside the hive as they dried off nectar into honey. A pretty impressive parlour trick!
Not sure that is the case on open mesh floors. where there is less need for anything other than a downward movement of moist air from the supers.

As for open mesh floors having an effect on varroa control...yer joking aren't you?

My own personal preference is for open mesh during the summer then poly inserts in over winter to act as solid floors. Helps prevent heat loss in winter due to convection caused by winds and freezing temps and the effects they must have on heat loss due overwintering bees on what essentially are open bottomed hives. Whilst I can understand the rationale for preventing dampness over winter in wooden hives, this is rarely an issue in poly hives. That the bees survive on open mesh is not in question, how much extra energy/heat they need to use/produce to survive on open mesh vs solid floors is an as yet unanswered question.

The good thing about open mesh is you can slide varroa boards in and out. Whilst I find the counts inaccurate, they do provide you with a quick simple method to get a rough indication of varroa levels.
 #11336  by AdamD
 28 Jun 2021, 07:05
"As for open mesh floors having an effect on varroa control...yer joking aren't you?" It's written - so it must be true! I assume that studies have been done to their effectiveness - and a few mites will fall through which is always a good thing.
The Paradise mesh floor has a significant amount of plastic, so the 'holes' are not that big, so easy for mites to survive the fall and stay in the hive; an expanded metal mesh must be more effective as there is more open space.

A wooden hive with insulated roof and mesh floor is usually dry and mould-free in spring for me. I wil usually have a super underneath the brood box over winter which would reduce the effects of wind on the colony.
 #11346  by MickBBKA
 28 Jun 2021, 23:21
I do have to disagree with you Nigel about the poly hives. They may not suffer condensation and neither do my wood hives with a bit of kingspan but the water ingress is ridiculous, sick of throwing rotten frames and mouldy comb out of poly hives in mid winter then spring.
 #11350  by NigelP
 29 Jun 2021, 08:16
It's strange that you are having these issues Mick as I know I'm using the same brand of poly hives and have no major issues with water ingress.
One thing I do before winter is ensure all the brood/super edges have had the propolis/burr wax etc scraped off both top and bottom sides so they fit flush. As the edges are quite hard then anything hard located between edges creates a gap through which water will creep in.
I also strap them down tightly as a brick is not sufficient weight due to the lightness of the hive parts.
 #11353  by AdamD
 29 Jun 2021, 09:00
If you guys are using the Abelo Mk 2's, they do suffer from water ingress that is supposed to have been resolved in the Mk 3's. (I am sure you know that).
Gaps developing under the crown boards of WBC's is a problem. Without the weight of a hive roof, there is no pressure to seal the propolis down and gap develops quite easily if the parts are not cleaned. And of course once there is a small gap, the bees try to fill it and add to the porpolis problem so on my WBC's at home I have a weight on top of a piece of celotex which sits on the crownboard.
Or, Mick, it could just be the driving wind from the NE!
 #11358  by NigelP
 29 Jun 2021, 16:21
Yes the mark2's have a supposed design fault that is easily solved by using tight ratchet straps. I have several and yet to suffer any serious water ingress. Vaseline along edges is also supposed to help if you don't strap them down tightly, like say using a brick on the top.
Alternatively just use the older style roofs with a large downwards overhang.