How much ventilation for a Nuc?

[drfraz]

I've just built two 5 frame nucs and was wondering how much ventilation they need.
They are 9mm ply with solid floors, 20mm entrance hole & deepish (150mm) roof to allow feeding & insulation. The floors can be removed fairly easily (well the one I didn't glue down!) so I could replace with mesh, but would rather add vents elsewhere as I only have small bits of mesh to hand (50x200mm), as well as for asthetic reasons.
Plans I've found vary from open mesh floors with holes everywhere to 6 frame nucs with thick walls and only a very small entrance.
So before I start drilling holes in my hard work any advice would be appreciated

 

[protheroe]

i use 12mm for nucs with a 20mm entrance hole and 150mm roofs.I dont use mesh floors and the bees do fine,they came through winter really well with plenty of stores left.For ventilation i place matchsticks under the front side of the feeder/crown board with 1 or more holes in the front of the roof to let water vapour out.

 

[user 6228]

i use 12mm for nucs with a 20mm entrance hole and 150mm roofs.I dont use mesh floors and the bees do fine,they came through winter really well with plenty of stores left.For ventilation i place matchsticks under the front side of the feeder/crown board with 1 or more holes in the front of the roof to let water vapour out.

Is it your intentition to provide only shelter from the wind? if so why not just use canvas. or nylon sheeting... 12 mm of plywood is a very poor at insulation, Please consider a small colony in a nuc needs to husband it resources. Heat being a major consideration.
You are providing less than 1/20th of the insulation that bees would have in a tree nest and the top ventilation is destroying the warm pocket of air at the top as well.

 

[beebreeder]

Bees are more resourcefull than we give them credit for, if they do not want the vents they just seal them with propolis. I have scraped numerous 2inch round floor vents that they had sealed and in some cases the mesh in the crownboard was sealed unless it had had fondant on during the winter and thats 12 mm ply nucs

 

[oliver90owner]

if they do not want the vents they just seal them with propolis

Yes, they most certainly do. But unfortunately this extra ventilation is often enforced on the colony at a time when 'sealing-up-holes duty' time has passed by - when they are clustering.

I was wondering why there were 1 or more holes needed in the roof. The roof must be a good fit if there is no clearance between it and the box.

Ventilation needs to be arranged to remove surplus water, not excessive thermal energy.

 

[protheroe]

if they do not want the vents they just seal them with propolis

Yes, they most certainly do. But unfortunately this extra ventilation is often enforced on the colony at a time when 'sealing-up-holes duty' time has passed by - when they are clustering.

I was wondering why there were 1 or more holes needed in the roof. The roof must be a good fit if there is no clearance between it and the box.

Ventilation needs to be arranged to remove surplus water, not excessive thermal energy.

i drill either a couple of very small holes or a single larger one in the centre.My nucs came through winter well.A beekeeping friend of mine had a nuc with no ventilation,the nuc died out.On inspection the box was full of mould and really wet.Wether this led to their demise i do not know but i dont think it helped

 

[Tom Bick]

Is it your intentition to provide only shelter from the wind? if so why not just use canvas. or nylon sheeting... 12 mm of plywood is a very poor at insulation, Please consider a small colony in a nuc needs to husband it resources. Heat being a major consideration.
You are providing less than 1/20th of the insulation that bees would have in a tree nest and the top ventilation is destroying the warm pocket of air at the top as well.

!2mm plywood is plenty for a nuc they overwinter well in them and as for the few I have done they seem to come through the winter strong.

I think it is all down to the health and strength of the bees in the hive that's important.

As for the ventilation solid floor is perhaps best I do have a couple of fancy Cedar nuc's with mesh floor's but they have a well fitted inspection tray so the floor can be closed off and one of the Cedar nuc's is for a one frame observation hive so it will need the mesh floor.