Floor depth...

[bjosephd]

Hello all…

Re-inventing the wheel here (floor).

Or at least enjoying teaching myself woodwork between inspections!

So… depth of floor. (i.e. distance between bottom bars and mesh/solid floor)

Dave cushion says most are 28mm-32mm!

The floor I have in my hand here has a depth of 19mm

I imagine 9mm is minimum - and also the ultimate avoidance of brace comb. But doesn't leave much space for crowded hives to congregate.

So, what do you suggest, and why?

Thanks!

BJD

 

[user 6228]

you need to maximise the vertical distance from the comb to the entrance to improve heat retention

 

[bjosephd]

you need to maximise the vertical distance from the comb to the entrance to improve heat retention

I quite agree with this notion…

In one hive I currently have a slatted rack between floor and BB, which actually keeps a good space between brood and entrance. But not sure if I am convinced that the bees will never make a mess of it (or worse still, hide queen cells in there!

I'm actually working on a version of JBM's underfloor entrance, so the distance from the entrance or the exterior at all will already be greatly increased since I am using a 9.75" depth box as a basis for the design.

So I'm thinking I'm going to be all good for heat retention, so wondering what else I should consider with regards to floor depth.

Thanks for the advice derek,

Any other thoughts on actual measurements?

Ideally I don't want brace comb on the bottoms of my frames… or is it sensible to leave enough space for queen cells so they are 'easy to find' hanging off the bottom?

Thanks all

BJD

 

[charlievictorbravo]

Most of my under floor entrances have planed 4"x2" as the main members. My home-made 14x12 hives have top bee space so I needed at least a beespace under the frames to allow the bees to move about. I think I ended up with a 10mm spacer around the UFE - I was concerned about wild comb coming down from the underside of the frames if I made a much bigger gap.

I'm not sure heat loss would be significant with a UFE - any draft would have to negotiate a right angle bend to get into the hive where the bees enter and the OMF is 4" (100mm) above the bottom of the UFE structure. If I position the hive accurately on my collapsible hive stand (also made out of 4"x2") the OMF is 8" (200mm) above any airflow under the hive.

I'd be interested to hear if larger gaps between the under side of frames and the OMF has lead to any problems with brace/wild comb being made there.

CVB

 

[bjosephd]

Thanks CVB…

Yep… my current thinking was around the 10mm mark.

I too will have a good 9" of wood below most of the floor, so like you've mentioned most air flow should be well below the mesh… this is why I'm thinking you might be more likely to get combo built as far down as possible as the 'outside' coolness is effectively much further away… which is of course my intention.

 

[oliver90owner]

Depth from frames to floor is the real measurement, shirley?

National with a deep timber floor and bottom space boxes will be considerably different than with the floor with shallow entrance and top space frames. Work it out.

 

[Vortex]

I make all my own floors ... all are open mesh. The standard space above the floor is approx. 22mm which is 18mm for the entrance block (square) plus 4mm for the grove into which the mesh is inset.

I also assembled over the winter 3 Thornes budget floors for the association. Again the space is 18mm, set by the square entrance block.
However, since Nationals are predominately bottom space you can add another 8mm.

If you're after the dimensions of the side runners for the floors, then from memory they're 22mm x 70mm, basically ripped 150mm deck board, so 1 off 2.4m length does approx 3 floors.

 

[bjosephd]

Yes exactly, oliver90owner…

So… depth of floor. (i.e. distance between bottom bars and mesh/solid floor)

BJD

I can of course 'work it out' once I have decided what gap I am going for between the frames and the floor… so far I have discovered suggestions anywhere between 9mm and 31mm, and so am wondering what people tend to go for and why… my Mann Lake hives are 19mm between bar and floor. Is there any good reason that the floors I make myself should be more or less.

I understand that top/bottom bee-space of course needs to be taken into account.

 

[bontbee]

you need to maximise the vertical distance from the comb to the entrance to improve heat retention

How does that affect things on an OMF - is the draft/heat loss through the entrance that significant, compared to draft/heat loss through an open OMF? Or have I completely missed the point....? Ta

 

[jenkinsbrynmair]

On all my underfloor entrances - distance between bottom bars and floor - beespace

 

[bjosephd]

On all my underfloor entrances - distance between bottom bars and floor - beespace

i.e. 9mm ?

 

[jenkinsbrynmair]

i.e. 9mm ?

Just the beespace as built into the brood box

 

[user 6228]

How does that affect things on an OMF - is the draft/heat loss through the entrance that significant, compared to draft/heat loss through an open OMF? Or have I completely missed the point....? Ta

its really the distance to the next significant horizontal opening. So that could be the varroa tray slot or the bottom of the floor.
its a balance of air resistance and the build up of buoyant air in the hive.
If the entrance has enough resistance then the heat builds up inside and then escapes at the next level down. The entrance can be closed down to restrict airflow but then the buoyant air escapes lower down.

Some hive designs(e.g. thornes budget) with OMFs put a large permanently open varroa slot at same level as the mesh and the mesh close to comb. This makes for higher heat losses.

With insulation at the level of a polystyrene hive or better the next opening down (e.g. varroa slot) needs to bee 100mm+ below the comb.

 

[charlievictorbravo]

On all my underfloor entrances - distance between bottom bars and floor - beespace

Well at least two of us agree!

Taking Derekm's point about distance from comb to the next lowest free air, the underfloor entrance will give you the recommended 100mm if you use if you use the 1½" x 4" side rails as suggested in "The Brynmair slant on the Dartington inspired floor" so the under floor entrance has another advantage we were unaware of!

CVB

 

[Finman]

I make all my own floors ... all are open mesh. The standard space above the floor is approx. 22mm which is 18mm for the entrance block (square) plus 4mm for the grove into which the mesh is inset.

.

That is good old measure. I use 20 mm.

The floor needs space that dead bees drop onto the bottom. In low gap bee bodies stay between frames, and lower parts will rotten and get mold in winter.

Then, when you make higher gap, bees start to draw drone combs in the cavity, and that works then as a real varroa nursery.

I use solid floors.
.

 

[oliver90owner]

So… depth of floor. (i.e. distance between bottom bars and mesh/solid floor)

Dave cushion says most are 28mm-32mm!

The floor I have in my hand here has a depth of 19mm

I imagine 9mm is minimum - and also the ultimate avoidance of brace comb. But doesn't leave much space for crowded hives to congregate.

This is really silly. Dave Cushman was correct. 22mm (7/8'') entrance plus about 8mm for bottom bee space. Very common. Total 30mm.

Upturned reversible National timber floor will have 11mm less distance, n'est ce pas? That would be about 17mm.

Top bee space would reduce those figures by about 8mm.

Wild comb below the frames depends on the bees. Some don't bother if near 40mm, some would brace at 10mm. Wild comb will be built if there is empty space and nowhere else for the bees to brood/store.

Bees should not be 'congregating' below the frames. Beek needs to give them more room or expect swarming shortly.

Finnmans point re dead bees should only be relevant for overwintering. They are in trouble if it occurs at any other time in the activecseason!

 

[bjosephd]

Thanks all… some nice clear answers there…

Seems I'm free to use whatever depth suits my woodworking aesthetics and wood availability (i.e., if there's a certain proportion of timber I can use for more than one build solution!).

Interesting what you say oilver90owner that they'll brace even the smaller gap if they so choose!

Talking of 'congregating', one of my hives are very much congregating outside the front entrance at night at the moment even though they have an 'empty' brood box above them… the other hive not so much, but with them I am experimenting with a slatted rack (which unfortunately I forgot to take measurements off before putting it in, at least for curiosity's sake).

Anyway, the bearding/congregating hive I am tempted to swap the boxes since they don't seem keen to move up like the other colony.

Amazing how different the 'personalities' of different colonies are.

 

[Poly Hive]

And just when you thought the water was clearing....

Dave collected a lot of info but not all of it....

The first poly hives, circa 1984 and on had "holes" in the floors some 10" x 10" centred in the middle of the floor, and the bees in general built drone comb from the bottom of the frames to neatly fill it. Even in the pre varroa days it was handy to minimise the drone levels by trimming off this comb. Now of course it would also reduce the mite burden. The depth from the bottom bars to the mesh would have been some 32-35mm ish.

PH