Spacers under crownboard

[Little John]

There does seem to be a breed of beekeeper who wants to follow a rigid 'cooking recipe' when keeping bees - "this is what you do/ don't do" - in a routine and inflexible way, rather than tailoring their actions according to the current status of the hive.

Bees heat the cluster, not the hives (except as a by-product) - so talk of "loss of heat" as something to be avoided at all costs is something of an over-dramatisation. Experimental colonies of bees have been kept in freezers for long periods at temperatures much lower than Britain normally experiences, and have survived.

If a hive is thought to be excessively humid - then ventilate it. Simples.

But run the figures before whacking-in a piece of hardboard or several of Swan Vestas' finest. A very thin gap - a millimetre or so, on one one side of the box only - can be achieved with used credit cards. These will vent more than enough humid air if left in place for a short period (but not permanently).

LJ

 

[oliver90owner]

LJ has it in a nutshell - do as the bees wantg/need. That is why I use no top ventilation at all with OMF.

Peripheral or central draughts in the roof are both detrimental to the bees' welfare, if not needed. One may be worse then the other dependent on where the cluster might be, but neither can be classed as good if there is already adequate ventilation.

What would the bees have done? The same as all through the summer, they would have propolised any possibility of a gap.

I would think 'glass quilts' came long after actual proper quilts, which were both absorbent and very slightly permeable for the very limited ventilation required. Much the same as a proper Warre, I would expect; mostly propolised (given sufficient time) but nevertheless still gas-permeable.

 

[Amari]

Commonly used in parts I believe to provide rapid access to the supers during a honey flow for the returning foragers and reduce congestion/traffic in the brood box. One of the supers is pushed forward enough to create an entrance. I do it sometimes but bees being bees some colonies use the extra entrance and others are reluctant.

The bees you see using the extra entrance are probably robbers

 

[user 6228]

...

Bees heat the cluster, not the hives (except as a by-product) - so talk of "loss of heat" as something to be avoided at all costs is something of an over-dramatisation. Experimental colonies of bees have been kept in freezers for long periods at temperatures much lower than Britain normally experiences, and have survived.
...

Each time it this is quoted "Bees heat the cluster, not the hives (except as a by-product) " I think "oh not again" . Heat is energy is sugar . If the hive conducts less heat then the bees dont need to replace that difference in lost heat from chemical energy stores (sugar).

if you dont believe me go see another physicist

This is also statement of mis leading half truths... based on chinese whispers from information originally gathered in uninsulated and nearly uninsulated hives, (i.e. where the bees have no alternative behaviour for survival ) from seriously flawed research.(thermolgy of wintering honeybees)
The survival at low temperatures is based on a contraction of results i.e. some large colonies have survived low temperatures, but what percentage died?

Low heat loss environments (e.g. poly) for bees have proven improvements in survival rates especially for smaller colonies. They have proven lower consumption of stores.

Dont believe me? ask ITLD...

in short wooden hives, even without the matchsticks, kill more colonies each year than polyhives.


Dont believe me? ask ITLD...

Like smoking 60 senior service fags a day is no garantee of lung cancer putting matchsticks under does not garantee colony extinction. But would you want to take the increased risk

Polyhives have half the heat loss of wood ...

but even polyhives lose more heat than a tree nest...

 

[Ely]

Each time it this is quoted "Bees heat the cluster, not the hives (except as a by-product) " I think "oh not again" . Heat is energy is sugar . If the hive conducts less heat then the bees dont need to replace that difference in lost heat from chemical energy stores (sugar).

if you dont believe me go see another physicist

This is also statement of mis leading half truths... based on chinese whispers from information originally gathered in uninsulated and nearly uninsulated hives, (i.e. where the bees have no alternative behaviour for survival ) from seriously flawed research.(thermolgy of wintering honeybees)
The survival at low temperatures is based on a contraction of results i.e. some large colonies have survived low temperatures, but what percentage died?

Low heat loss environments (e.g. poly) for bees have proven improvements in survival rates especially for smaller colonies. They have proven lower consumption of stores.

Dont believe me? ask ITLD...

in short wooden hives, even without the matchsticks, kill more colonies each year than polyhives.


Dont believe me? ask ITLD...

Like smoking 60 senior service fags a day is no garantee of lung cancer putting matchsticks under does not garantee colony extinction. But would you want to take the increased risk

Polyhives have half the heat loss of wood ...

but even polyhives lose more heat than a tree nest...

I think some poly hives are better than others. My pains poly 14 x 10 melts snow off the top of the roof faster than my insulated cedar commercial. On that note. Could you recommend me a better poly hive, not necessarily 14x10?

 

[Amari]

I think some poly hives are better than others. My pains poly 14 x 10 melts snow off the top of the roof faster than my insulated cedar commercial. On that note. Could you recommend me a better poly hive, not necessarily 14x10?

As I posted a couple of weeks ago, snow melted off MB polyhive but not off 6 wooden Nationals with Recticel insulation under the roof.

 

[itma]

I think some poly hives are better than others. My pains poly 14 x 10 melts snow off the top of the roof faster than my insulated cedar commercial. On that note. Could you recommend me a better poly hive, not necessarily 14x10?

I think Pains roof is too thin.
The top insulation needs to be better than the sides!
So, I 'waste' a super with Kingspan/Celotex above my (proper) crownboard.
Thanks to whoever it was (derekm?) that assured me that the Beehive Supplies roof should fit nicely. I expect to be getting one ...

 

[Ely]

I think Pains roof is too thin.
The top insulation needs to be better than the sides!
So, I 'waste' a super with Kingspan/Celotex above my (proper) crownboard.
Thanks to whoever it was (derekm?) that assured me that the Beehive Supplies roof should fit nicely. I expect to be getting one ...

I've done the same, put a super on with insulation

 

[notaeab]

some put small sticks i.e. matches under crown boards that the bee seal up so not needed ! but the roof should not touch the crown board as it causes condensation if it does

 

[richardbees]

some put small sticks i.e. matches under crown boards that the bee seal up


No, they don't.....

 

[PBee]

The bees you see using the extra entrance are probably robbers

Not in a strong hive. In the US some beekeepers use an entrance eke between each super (Imrie Shim) as an alternative to staggering supers. As well as reducing congestion in the brood box one of the reasons given is that it makes it easier for the bees to dry out the nectar in a strong honey flow/tall hives. Sounds logical to me especially for poly/plastic hives.

 

[Little John]

Each time it this is quoted "Bees heat the cluster, not the hives (except as a by-product) " I think "oh not again" . Heat is energy is sugar . If the hive conducts less heat then the bees dont need to replace that difference in lost heat from chemical energy stores (sugar).

So what ? They are quite capable of replacing any lost heat.
They are not living on a knife edge where every last therm counts. "Bees heat the cluster, not the hives (except as a by-product) " is a perfectly true statement. If such true statements offend you - take a pill.

in short wooden hives, even without the matchsticks, kill more colonies each year than polyhives.

Well - that's not only a silly statement to make, as the number of wooden hives in existence dwarfs the number of poly hives - so if 'the death rate' was uniform across all hive types, one would expect that to be true, just on numbers alone - but it's a misleadingly dishonest statement:
you are saying that it is wooden hives that kill colonies - not starvation; not disease; not too many inspections by beginners in deepest winter; not attempting to over-winter colonies which are too small; not failure to ensure sufficient stores, etc etc - none of those - it is just the use of wooden hives, instead of polyhives. What rubbish. It is never the hives themselves which kill, it is how they are used or misused in conjunction with other beekeeping practices.

People have been keeping bees in wooden hives for generations, without undue problems. People lose colonies because people lose colonies - not necessarily because of the material used in their hive construction.
All my hives are wooden hives. I will continue to make wooden hives. I consider that wooden hives are 'fit for purpose' - they are cheap to make and robust enough to stand harsh treatment. If bees need to burn more sugar than in a polyhive, let them burn more sugar. They'll cope.

Dont believe me? ask ITLD...

Why do you keep saying 'ask someone else ?' Are you relying on weight of numbers to support a flimsy argument ?

Like smoking 60 senior service fags a day is no garantee of lung cancer putting matchsticks under does not garantee colony extinction. But would you want to take the increased risk Polyhives have half the heat loss of wood ...

If you had actually read my post to read what I had said, rather than what you think I may have said, then you would know that I said NOT to use matchsticks, but rather credit cards (on one side only) to give a 1mm gap, for a time, but not permanently.

"... would I want to take the increased risk ?"

Every decision, every action a beekeeper makes involves some 'risk' - it goes with the territory, as our American friends are fond of saying. Ah - now, Americans - those are the people to preach to regarding top ventilation: they favour whacking great holes at the top !

LJ

 

[richardbees]

In the US some beekeepers use an entrance eke between each super (Imrie Shim)

presumably they don't have problems with robbing or wasps!

 

[itma]

... In the US some beekeepers use an entrance eke between each super (Imrie Shim) as an alternative to staggering supers. As well as reducing congestion in the brood box one of the reasons given is that it makes it easier for the bees to dry out the nectar in a strong honey flow/tall hives. Sounds logical to me especially for poly/plastic hives.

Thanks for that.
If we get a proper summer, I'll now have a decent answer to the question "wtf is THAT?"

 

[user 6228]

So what ? They are quite capable of replacing any lost heat.
They are not living on a knife edge where every last therm counts. "Bees heat the cluster, not the hives (except as a by-product) " is a perfectly true statement. If such true statements offend you - take a pill.



Well - that's not only a silly statement to make, as the number of wooden hives in existence dwarfs the number of poly hives - so if 'the death rate' was uniform across all hive types, one would expect that to be true, just on numbers alone - but it's a misleadingly dishonest statement:
you are saying that it is wooden hives that kill colonies - not starvation; not disease; not too many inspections by beginners in deepest winter; not attempting to over-winter colonies which are too small; not failure to ensure sufficient stores, etc etc - none of those - it is just the use of wooden hives, instead of polyhives. What rubbish. It is never the hives themselves which kill, it is how they are used or misused in conjunction with other beekeeping practices.

People have been keeping bees in wooden hives for generations, without undue problems. People lose colonies because people lose colonies - not necessarily because of the material used in their hive construction.
All my hives are wooden hives. I will continue to make wooden hives. I consider that wooden hives are 'fit for purpose' - they are cheap to make and robust enough to stand harsh treatment. If bees need to burn more sugar than in a polyhive, let them burn more sugar. They'll cope.



Why do you keep saying 'ask someone else ?' Are you relying on weight of numbers to support a flimsy argument ?



If you had actually read my post to read what I had said, rather than what you think I may have said, then you would know that I said NOT to use matchsticks, but rather credit cards (on one side only) to give a 1mm gap, for a time, but not permanently.

"... would I want to take the increased risk ?"

Every decision, every action a beekeeper makes involves some 'risk' - it goes with the territory, as our American friends are fond of saying. Ah - now, Americans - those are the people to preach to regarding top ventilation: they favour whacking great holes at the top !

LJ

Your statements and rebuttals are misleading to the less knowledgeable.

More heat loss increases the probabilty of colony loss from starvation and disease. Heat flow is devoid of intention. The bees generate heat and have behaviours to reduce heat loss and that is it.

These behaviours have limits and restrictions of effectiveness particularly for smaller colonies. These behaviours originated in a highly insulated environment (tree nests, which have several times the thermal resistance of a standard wooden hive).

To use language that gives the impression that the thermal resistance of the hive/nest is of little consequence is inaccurate and misleading

Using thin wood in a high heat loss configuration (i.e. without substantial insulation) increases the probability of colony loss, reduces honey yield compared to poly. This is from the information i have gleaned from ITLD (on his own colonies) and other sources (scientific research).

The statement that "they are capable of replacing any lost heat" is careless and inaccurate. They can only replace heat at a rate and for a duration limited by the bees available and their resources. Extra heating demand has been identified as "Stress" and stress is known to increase susceptability to disease such as nosema.


As regards "wooden hives for generations", thats really small beer as bees have been in highly insulated environments in this country and northern Europe since the last ice age.

 

[drstitson]

"What are current thoughts worthy or not?"

see my poll here back just over a year ago (quick link provided on letter page in the latest issue of Beecraft).

a 2.2mm matchstick results in a 40cm2 gap around the top of the brood box.

would you overwinter your home with an open loft hatch in each bedroom?

3-4mm hardboard is obviously worse.


most enlightened beeks are using top insulation, open floors and no BBKA approved matchsticks.

 

[alanf]

until 1946, no one really ventilated the top crown board, until Wedmore published his 1947 book "The ventilation of bee-hives" in which he said hives needed ventilation as langstroth proposed in 1852 quote " a small week colony need through ventilation"

Interesting observation. As it happens I was looking through Edwardian bee books and journals. No mention of raising crown board that I saw. Is there really nothing in print before Wedmore?

Difficult to prove a complete absence of course, but adding top ventilation was not a common practice. Plenty of references to sacking and other materials as top insulation though, and not a lot of dissent, so presumably widespread.

 

[Russel]

Just to put more cats amongst the pigeons, went to assoc apiary Sat morn with the AM to put fondant on 6 colonies, on OMF's & carpet quilts. 2 of them were dripping neh raining from the roofs & quilts sodden, bees appeared to be okay. Scratched heads abit, only difference was the roof internal boards being MDF on the 2, the MDF presumably acting as a sponge. Changed to OSB boarded ones, will check later in week.
So, still need to be vigilant even when all is done by the current "book".

Russ

 

[itma]

Russel - if warm (bee) air can permeate through to the underside of the roof metal, you will get condensation there, which will then drip and soak back down.
You really need what builders call a "vapour barrier" - and it needs to be warm itself to avoid being the site for condensation.
An impermeable (like plastic, preferably see-through) coverboard with good insulation above does the job very nicely. Note that I am not confusing the clear coverboard with a "quilt" - which term I reserve for insulation. And, for insulation effect, you won't do better than insulation board (like Kingspan, Celotex, etc) - which also gives an insulated vapour barrier!
The alternative method of reducing nuisance from under-roof condensation is to give more ventilation *above* the insulation. The more permeable your crownboard (or the bigger its holes) the more ventilation you need between roof and crownboard.
Much better to reduce the water vapour getting to the cold underside of the roof.

 

[Russel]

Thank you Itma,