Winter insulation?

[enrico]

The way I see it and always have done is that if the colony has enough stores it will alter the temperature as it needs to. If the hive is totally uninsulated then they will use more food, but if you have provided it then there is no problem,
If you are going to insulate then do you provide less food? If so then why bother?
The only advantage that I can see for insulation is to build bees up quicker in spring because they can start expanding a couple of weeks earlier, but hey, they catch up! If you have a spring flow then insulate. I don't have a flow until Hawthorne comes out so what is the point? I get honey, my bees live and we all seem happy!
E

 

[TryingToLetThemBee]

Ship: I meant to edit out "in the UK" as a red flag. Too bad; the point is we have "Palm Beach" winters near to cluster temperature.

brianmc: I'm not derekm but I have just made up a 125mm crownboard made of a ring of 6mm ply to National dimensions around Kingspan. No beespaces yet. The bees will not eat the foil, but will find any holes. I have not "topped and tailed" it so as to get a better seal, but will probably "top" it for some protection. I'll put it over a clear solid board which has no top beespace

 

[TryingToLetThemBee]

I get honey, my bees live and we all seem happy!
E

My aim in starting out (naive optimist) is 100kg hives... I want them roaring out of the gate with as much ivy still in the brood box as possible.

 

[user 6228]

The way I see it and always have done is that if the colony has enough stores it will alter the temperature as it needs to. If the hive is totally uninsulated then they will use more food, but if you have provided it then there is no problem,
If you are going to insulate then do you provide less food? If so then why bother?
The only advantage that I can see for insulation is to build bees up quicker in spring because they can start expanding a couple of weeks earlier, but hey, they catch up! If you have a spring flow then insulate. I don't have a flow until Hawthorne comes out so what is the point? I get honey, my bees live and we all seem happy!
E

better survival margins ... smaller or disadvantaged colonies do a lot better. Vilumstad 1973. There are limits to providing them more and more food as it gets colder. It also adds stress. Stress means more disease.

 

[user 6228]

Since this thread has Derekm's attention...

With regard to "easy wins"... Insulating the top of the hive (crown board) seems to offer the most benefit with the simplest interventions for someone with wooden national hives.

I've bought 50mm Kingspan to provide insulated "crown boards" to my hives and I'm trying to come up with a robust solution without reducing the benefits of the insulation too much.

The simplest solution is to use a 460mm square slab of kingspan instead of a crown board but that won't be robust around the edges. So I would like to frame it.

After that I am worried about the silver paper surfaces and how fragile they are. I can't scrape them off with the hive tool. Will the bees eventually chew through them? A skin of plywood would act as a cold bridge I guess but is it significant? I'm considering this a permanent replacement for normal crown boards.

View attachment 8949

Some advice would be great if you can. While I see the thermal benefits of a fully insulated outer cover, it would be inconvenient to work with compared to replacing the crown board with something like the above.

Thanks!

Kingspan appears to have a thinner foil surface than recticel. However I have only one small gnawed hole in a Kingspan branded roof/crown board, probably started by damage. I have none so far in Recticel. I use this stuff all the time as a combined crownboard/roof see avatar

 

[brianmc]

Kingspan appears to have a thinner foil surface than recticel. However I have only one small gnawed hole in a Kingspan branded roof/crown board, probably started by damage. I have none so far in Recticel. I use this stuff all the time as a combined crownboard/roof see avatar

Yeah, I can't imagine the surface of Kingspan allowing for years of use, scraping off brace comb and getting knocked about.

Have you an intuited notion of how much of my insulating efforts I'd be wasting if I put a skin of plywood in?

 

[TryingToLetThemBee]

brace comb

Unless you are VERY non-interventionist, that should not be an issue.

Thinking aloud, how about a thinner, renewable, skin of plastic sticky film?

 

[pargyle]

OK ... I've just read the thread from April ... that didn't really get anywhere either but two of the posters in that thread (who actually used heaters in their hives) are still active on the forum ... with a bit of luck they will be along to give us an update of whether they will be heating again this year.

My proposed heat source (if I use them) are a pair of 12v heaters intended for warming motorcycle handlebars. They are 12v and only 3w ...

http://www.ebay.co.uk/itm/370882692507?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

The control unit is another ebay job:

http://www.ebay.co.uk/itm/380706189510?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Which will allow a setting for both a cut in at a temperature and/or a cut out but what I am thinking is that I will couple this with a 12v relay like those that keep your car headlamps on after the ignition is switched off so that the heaters just warm for a short period and then cut out ... to be triggered again if the temp in the hive remains low.

Powered by a 12v leisure battery (which I keep for various uses at home).

 

[Little John]

Thinking aloud, how about a thinner, renewable, skin of plastic sticky film?

But why sticky ? (someone's been watching Blue Peter )

Folk have been placing a layer of bog-standard thick (polytunnel grade) polythene directly over the top of long hives for years. The bees propolise it, sure, but that doesn't present any problems. It would also help to break any thermal bridging - if that should be a concern.

LJ

 

[TryingToLetThemBee]

Yeah, I can't imagine the surface of Kingspan allowing for years of use, scraping off brace comb and getting knocked about.

Have you an intuited notion of how much of my insulating efforts I'd be wasting if I put a skin of plywood in?

Envelope, not intuition, and a conservative estimate. I make it that it would mullah it: can someone check?

Sum: losses = conductive area / thickness * conductivity

Ply: 6mm(approx)*2m/6mm(approx)*0.2 = 0.4 (W/K I think: not important)
Kingspan 0.5m*0.5m/125mm*0.033 = 0.06. So 15 times the losses and 125mm becomes equivalent to 8. Yikes: thanks for that.

<ADD>Wrong: 0.4/0.06 is 6.7, not 15. So 125mm is reduced to more like 17.</ADD>

 

[TryingToLetThemBee]

But why sticky ?LJ

Less fiddle, but thanks. I have wrapped the edges with silver tape, so peeling a cover should not take off the foil. I am 2-checking that sum above; it seems to be right <ADD> Corrected: see above</ADD>, so a ply skin is really thermally leaky.

 

[Finman]

The way I see it and always have done is that if the colony has enough stores it will alter the temperature as it needs to. If the hive is totally uninsulated then they will use more food, but if you have provided it then there is no problem,
If you are going to insulate then do you provide less food? If so then why bother?
The only advantage that I can see for insulation is to build bees up quicker in spring because they can start expanding a couple of weeks earlier, but hey, they catch up! If you have a spring flow then insulate. I don't have a flow until Hawthorne comes out so what is the point? I get honey, my bees live and we all seem happy!
E

Holy ship, again! What a knowledge after all these all these discussions!!

- In Finland we use to feed sugar 20 kg per hive for winter.

- In USA , in some states, local beekeeping universities use to advice 3 boxes food, what makes 60 kg winter food.

- In Alaska they are not able to over winter hives. University of Fairbanks recommends to kill colonies before winter.


If you have 20 hives, you spend 400 kg sugar to hives. According US recommendation you would use 1200 kg sugar!!!!

 

[TryingToLetThemBee]

Sorry for the hyperactivity, but the above is a VERY conservative estimate, based on a heated cavity extending across the entire area of the Kingspan. More reasonably, given the 17" internal dimension, the heat has to travel an extra 14mm each side through the ply skin, cutting its losses to 6mm*2m/20mm*0.2=0.12, roughly trebling the losses and reducing the effective thickness to 40mm from 125mm IF the lid is on square.

 

[Finman]

.
I have learned in this forum, that quite several beekeepers cannot get their colonies big enough because they do not understand the wisdom of warm hives.

And what is the reason to that.......

Their teachers do not know how to build up the colony during SUMMER!!!! ...Read SUMMER!

To understand heat economy and bees' need to save energy is not limited only to winter. It works as well in summer.

- too small colony in a box without dummy board
- mesh floor

- small colony and then empty super over the colony too early + mesh floor

- to feed brood space too full of sugar or waiting that bees collect honey for winter which fills brood room.

- Too much ventilation and too much empty space = hive is too cold to expand



My experiences during last 10 years show that with pollen patty and with electrict heating I can get 3 fold build up in Spring in big hives.

Extra heat and warm hive helps the cluster expand and make 3 times more brood. That derives from sphere volume formula

 

[Finman]

.
Ideal insulation = practical insulation to nurse hives

In wooden boxes insulation makes hives very heavy.
I have beautifully made wooden box which's weight full of honey was 52 kg. To morrow I carry it to dumping place.
It means that half of weight was from hive box.
To morrow I carry it to dumping place.

In modern poly hives the box weight is 1000 g. The wall is 4 cm.

Those polyhives which I bought 20 years ago, they had 2 cm wall. However they were much more better that 3 cm wooden wall.

Polyboxes reduced winter food consumption -35% compared to wooden box. It means that no beed to feed hives in spring. There are food enough after winter.

Do you buy 400 kg sugar or 600 kg? = work and pure money.

In summer I use those 45 y old wooden boxes as supers.

.

.

 

[Little John]

.
In wooden boxes insulation makes hives very heavy.

Sure - but they're beehives - not suitcases.

If you need to move them a lot - put 'em on a trailer.

If you don't - what's the problem ?

LJ

 

[TryingToLetThemBee]

.

- to feed brood space too full of sugar

It's REALLY good to have you back posting about more than saunas. I have wondered where you were in the threads about boxes stuffed with sugar.

I am going to insulate despite concerns about keeping the colony active during Palm Springs winter (which concerns I cannot disprove with any research I have found).

At some point, when the weather finally turns and after this incredible ivy flow, I am going to stuff the brood box as well and start weighing to build a data set. This is my first winter, and I am learning EVERYTHING. Then, in spring, if the box is heavy, I will remove some of the remaining ivy/thymolated syrup mixture and give them back some drawn comb.

 

[tonel]

I currently have a standard crown board on with a rapid feeder over the centre hole (other hole covered) surrounded by a shallow eke. Once feeding is done am planning to cover the feed hole and put in some insulation to fill the eke, then roof on as normal. Standard wooden National with OMF. That's my plan so far..

 

[Finman]

- what's the problem ?

LJ

I have no problems.

. Problems are there

 

[Davelin]

I currently have a standard crown board on with a rapid feeder over the centre hole (other hole covered) surrounded by a shallow eke. Once feeding is done am planning to cover the feed hole and put in some insulation to fill the eke, then roof on as normal. Standard wooden National with OMF. That's my plan so far..

Seems sensible to me; this all seems to be getting over technical as far as I can see.
Once finished feeding I put a square of insulation (polystyrene or kingspan type) to fit inside the frame of the feeder board/eke.
I know this is not the coldest part of the country, but last winter was quite chilly and all my hives got through.