Insulation covers

[madasafish]

Actually, since keeping bees, I have rued the fact so many times that I didn't learn more about woodcrafting when I was growing up!

Well yes: I am the same. But the bees don't mind my bodges...

 

[jackbee]

Actually, since keeping bees, I have rued the fact so many times that I didn't learn more about woodcrafting when I was growing up!

me too, but i'm learning fast, been one of the enjoyable bonuses of beekeeping so far. Lesson learnt yesterday making a ply nuc - I can't saw straight yet , so it is a cpl mm less height than it should be thanks to planing 2 nuc sides to same size - luckily frames still seem to fit with correct bee space - we'll see next year when I get to use it.

Good to know I'm not the only skip surfer here. Stopped on Friday night to pick up some insulation off cuts. The builders were most intrigued when I said it was to keep the bees warm over the winter. Is skip surfing another skill a beekeeper needs?

Another new skill picked up - got some ply this week for crown boards, just need some kingspan now - should have a sticker on car - "Warning - I slow down for skips"

 

[m100]

Wickes do small sheets of Kingspan 1200 X 450 X 50mm @ £5ish. Cuts into 3 insulation slabs for Nationals.

My national hives internally are 360 x 410mm. Have just finished making a batch just now.

Tape the edges with gaffer/duck tape to seal them.

Wickes do full size (8x4) sheets in 25mm for under 20 quid, enough for 10 hives (as squares but a lot of offcut to do a few more). Can be interesting transporting a full sheet though

Cut 435mm square for fitting into the recess in T*****s roofs.

 

[Erichalfbee]

Is skip surfing another skill a beekeeper needs?

Good stuff to be found in skips
Conversely ....One thing I have learned is to order your skip ONLY when you have enough stuff to fill it to the brim straight away!!!
Might make a good film covertly catching the dumpers!

 

[nemphlar]

I've discovered pound shop Formica iron on to any type of poly works a treat for top insulation boards

 

[alanf]

Wickes do full size (8x4) sheets in 25mm for under 20 quid, enough ftor 10 hives (as squares but a lot of offcut to do a few more). Can be interesting transporting a full sheet though

Cut 435mm square for fitting into the recess in T*****s roofs.

The recess in the flat roof provides ventilation which filling it would block. I think a better option to use the insulation is full width with a 460mm square.

Transporting is easier after cutting the sheet. Take a tape measure, rip saw and straight edge, cut a 460mm strip down one side in the car park. Just don't try it on windy day.

 

[Tom Bick]

I have constructed a couple of rooves filling the void in the rooves with insulation and doing away with the roof ventilation I have covered the insulation with 6mm ply and fitted a 8mm pice of timber around the edges giving either one or two beespace above the crown board depending on the type of crown board. I see little point of the roof ventilation and the large cavity in the roof as to me this is left over from solid floors. The hives with this modified rooves have performed well with no problems to hive and bees and will convert all my rooves when they become available.

 

[Poly Hive]

Why does the ventilation in the roof matter when the OMF floor is in place?

Please remember a ventilated floor should be coupled with top insulation.

When I ran some timber hives the insulation for the roofs was cut to fit the roof so when the roof came off the insulation didn't go flying off in the breeze.

PH

 

[alanf]

I see little point of the roof ventilation and the large cavity in the roof as to me this is left over from solid floors.

You.are almost certainly right that that's why ventilation was mainly designed in there. And we are probably due a rethink of what the best roof is for an omf wooden hive.

My thinking was that some air circulation under a protective metal roof is a good idea. The steel buildng roof is common in hot climates but always has a void with air circulation between steel and ceiling. The roof takes the heat of the sun but the temperature above the ceiling is closer to ambient air. Insulation below that is more efficient if the temperature gradient starts with ambient, not hot metal.

Your design has an air gap below the insulation if I read it right, which works but is subject to convection and draughts in an area you're trying to keep warm. The battens in the average roof are not a great seal to the crown board but you have a ply layer to improve that, which sounds like a good solution.

My thoughts were to keep to the standard roof as much as possible. It gives interchangeability and economy if you're buying materials. Use a 460mm square sheet of celotex/kingspan underneath tape sealed at the edges. So far this has rested on the crown board with ply scraps over the holes if it's a multi purpose one. Taking the insulation to the full box width leaves just the joint between crown board and insulation. Insulation in a super has gaps between super and insulation plus between super and crown. A 25mm thick sheet fits under the standard roof and leaves the roof still reasonably weatherproof. 50mm might be better but reduces the skirt overlap. It's a compromise and 25mm is still a lot of insulation compared with wooden walls.

Next experiment is celotex crown boards. Take the 460mm square and tape a batten around the outside to give a beespace underneath. No air spaces between bees and insulation. Whether it's an improvement or needs something like a poly sheet bonded to the bottom we'll find out over the winter.

 

[northernsoul]

sorry don't get it.

I think most of us have kept bees in very cold temps -19 for me in December 2010 was the record. No insulation and no problems.

What exactly is the benefit of all this insulation? I can only think that it might be slightly less stores consumed?

 

[Erichalfbee]

I put 50mm of kingspan in a super and roof on top of that.
Perhaps fitting the insulation onto the roof battens and using a deep roof might be better?

 

[user 6228]

sorry don't get it.

I think most of us have kept bees in very cold temps -19 for me in December 2010 was the record. No insulation and no problems.

What exactly is the benefit of all this insulation? I can only think that it might be slightly less stores consumed?

Are colony survival and profit the only valid metrics?

Proper insulation makes a considerable difference to the stores consumed, but much more than that is stress on the bees. On top of the varoa, the insectcide load, nosema, chalk brood stresses, there is the stress of maintaining heat output in the colony.

one adds insulation to reduce the overall stress on the colony to increase the margin for survival against all stresses that might overcome the colony.

One might argue that it is good husbandry of livestock to reduce the stress on the livestock where feasible and practical.

 

[user 6228]

Why does the ventilation in the roof matter when the OMF floor is in place?

Please remember a ventilated floor should be coupled with top insulation.

When I ran some timber hives the insulation for the roofs was cut to fit the roof so when the roof came off the insulation didn't go flying off in the breeze.

PH

for best effect the insulation should be sealed around its edges to the sides of the roof.
one should also consider taping the box to box joins on the outside.

 

[m100]

My thoughts were to keep to the standard roof as much as possible. It gives interchangeability and economy if you're buying materials. Use a 460mm square sheet of celotex/kingspan underneath tape sealed at the edges. So far this has rested on the crown board with ply scraps over the holes if it's a multi purpose one.

As PH has said such an implementation is another thing to faff around during an inspection and will either blow away in a light breeze or get damaged. Fitting insulation as an interference fit in the roof recess means it just stops there, and does the job all year round. It also ensures the roof fits with normal overlap of the hive boxes, reducing the chance the roof itself will blow off

The benefits of roof insulation will be seen all year round, less heatloss in winter (no melted ice / snow patches in middle of roof) meaning reduced consumption of stores, and less heat gain in summer so fewer water carriers to keep the hive temp down.

 

[oliver90owner]

so fewer water carriers to keep the hive temp down

Agree, but, ha ha, not this year!!!

 

[itma]

Why does the ventilation in the roof matter when the OMF floor is in place?

Please remember a ventilated floor should be coupled with top insulation.
...

Its *roof* venting, not *hive* venting that was being considered there -- this is venting *above* the insulation that is top-sealing the brood box. This venting is important to prevent wood rotting under the metal cover - no matter with poly roofs!
I put a scrap of tile on top of the insulation to ensure that there must be a (small) airspace above the insulation.

sorry don't get it.

I think most of us have kept bees in very cold temps -19 for me in December 2010 was the record. No insulation and no problems.

What exactly is the benefit of all this insulation? I can only think that it might be slightly less stores consumed?

For me one important benefit with wooden hives is to help avoid condensation above the cluster, where it would drip onto the bees, to their disadvantage, even harm.
Keeping the crown board just fractionally warmer means that any condensation will be in a safer place. So I use a (see-through) polycarbonate crown board with a Kingspan super above in order that the bees can most easily warm the crown board above them, and preventing condensation directly overhead.


The stores consumption thing is actually a bit counter-intuitive.
As best as I can make out, when it gets cold enough in the hive for the bees to cluster there is actually a step down in the consumption.
As it gets colder, the bees cluster more tightly and there is relatively little increase in the stores consumption until it gets really bloody cold inside the hive, something like minus 5 or 10C (which isn't very common inside most UK hives).
Thus the highest consumption seen in the UK is likely to be in mild damp winters ... unless it gets seriously cold for months on end (1963?)
An important advantage of any insulation (and polyhives) should be an earlier, stronger start to brooding and thus a better start to the new season - but that is a different matter to stores consumption.

 

[alanf]

Its *roof* venting, not *hive* venting that was being considered there -- this is venting *above* the insulation that is top-sealing the brood box. This venting is important to prevent wood rotting under the metal cover - no matter with poly roofs!

Agree. Several ways of applying in detail, they all have advantages/disadvantages depending on simplicity to make, handling, versatility, roof fit or whatever. Or you could vapour seal more effectively or put up with some rot dependant on how cheapo and water soluble your roof material is.

As far as winter temperatures are concerned, I read somewhere that Canadians who store their hives under cover for the winter use a constant 5 degrees C. Empirically the lowest stores use for their varieties, higher or lower increasing consumption. The 'perfect' temperature may vary a little for others but it won't be far off.

 

[Amari]

sorry don't get it.

I think most of us have kept bees in very cold temps -19 for me in December 2010 was the record. No insulation and no problems.

What exactly is the benefit of all this insulation? I can only think that it might be slightly less stores consumed?

Me too. I have never used insulation, even after moving to OMF floors six years ago. Insufficient stores, damp, and forgetting to remove the queen excluder are the only hazards I recognise.

 

[Lorenz]

I bought a load of those insulating quilts in the thrns sale last year. They were rubbish. The hives were too damp and I lost a lot of bees.

 

[Tom Bick]

You.are almost certainly right that that's why ventilation was mainly designed in there. And we are probably due a rethink of what the best roof is for an omf wooden hive.

My thinking was that some air circulation under a protective metal roof is a good idea. The steel buildng roof is common in hot climates but always has a void with air circulation between steel and ceiling. The roof takes the heat of the sun but the temperature above the ceiling is closer to ambient air. Insulation below that is more efficient if the temperature gradient starts with ambient, not hot metal.

Your design has an air gap below the insulation if I read it right, which works but is subject to convection and draughts in an area you're trying to keep warm. The battens in the average roof are not a great seal to the crown board but you have a ply layer to improve that, which sounds like a good solution.

My thoughts were to keep to the standard roof as much as possible. It gives interchangeability and economy if you're buying materials. Use a 460mm square sheet of celotex/kingspan underneath tape sealed at the edges. So far this has rested on the crown board with ply scraps over the holes if it's a multi purpose one. Taking the insulation to the full box width leaves just the joint between crown board and insulation. Insulation in a super has gaps between super and insulation plus between super and crown. A 25mm thick sheet fits under the standard roof and leaves the roof still reasonably weatherproof. 50mm might be better but reduces the skirt overlap. It's a compromise and 25mm is still a lot of insulation compared with wooden walls.

Next experiment is celotex crown boards. Take the 460mm square and tape a batten around the outside to give a beespace underneath. No air spaces between bees and insulation. Whether it's an improvement or needs something like a poly sheet bonded to the bottom we'll find out over the winter.

Yes I am all for a slab of 460mm square insulation over the crown board on my standard rooves it just seemed easier to build it into the roof space occupying this void that seems a waste of space and left over from a time when we had solid floors.

Insulation will work in both ways it will keep heat in and heat out generated from the metal roof covering. I only go for 25mm insulation I don’t think you get a great deal more benefit from 50mm+ but 25mm is more difficult to get from skips so I just buy it when needed.

I have a one or two beespace gap between top of crown board and underside surface of roof depending on crown board, because I reverse my crown boards removing brace comb and instead of brushing the bees away I sometimes leave the feed hole open this gap will also gives me a space if I need to emergency feed with granulated sugar sprinkled on the crown board. However the bees often attach crown board and roof with small amounts of brace comb if I leave things to long and if I leave the feed hole open at the wrong times it simply requires a bit of leverage from the hive tool to loosen.

I don’t see my one or two beespace gap a problem nor the fact that the seal from roof to crown board is not 100% but to me it’s the say 30mm gap from crown board and underside of roof with roof vents that makes no sense to me with OMF floors.