# Screened bottom on Warre hive



## beez2010

You might be interested in this website. You don't need to buy anything to see everything (although many people have built their own hives and then purchased screened floors and/or other accessories from us). You might find the FAQ to be of particular interest.

Chris Harvey--Teakwood Organics

www.thewarrestore.com


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## Kelbor

So, I may be looking at your screened bottom wrong but isn't the entrance shape and angle been changed? On the Warre specs he indicates a width of 4 3/4" and depth of 1 3/4" (with the width of walls of the overlying box at 3/4" gives the bees an entrance of 3/4"). I also thought I read somewhere that the angle of the ramp from the entrance board into the hive played some sort of role. Any thoughts.....?


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## Beethinking

From my experience most Warre beekeepers are opposed to screened floors for various reasons. Some cite too much ventilation, arguing that feral colonies rarely choose such cavities. Others argue that it disrupts their ability to heat or cool the hive. Some just don't like the fact that it deviates from Warre's design. 

Personally I don't use screened bottom boards on any of my 20 some odd hives (other than my Langstroth hive, which I keep closed at all times). I live very close to you up here in Portland, Oregon, and my hives are overwintering successfully and thriving. 

Best,
Matt


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## beez2010

Kelbor,

I am not sure where you got your specs. Maybe I am misunderstanding you. The entrance specs of 18 cm2 is given on page 48 of BFA. Warre typically used an entrance of 120mm x 15mm. Our floor creates an entrance of 180mm x 10mm and works just fine as-is.

The standard Warre hive with its _flat_ alighting board allows water to accumulate during rain showers which drowns lots of bees afterward, much like flat landing boards on Langs do. Our angled landing board prevents that.

To each their own, but I can't think of _one_ legitimate reason _not_ to use a screened floor on a Warre and lots of reasons _to_ use one.


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## Michael Bush

Warre would definitely not approve of an open mesh floor. You're trying to maintain the heat and smell of the brood nest in a Warre.


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## beez2010

Since heat rises, the Warre hive is designed to the approximate size of the cluster, _and_ there is a quilt box at the top that strictly limits the amount of air that can exit the top of the hive (therefore also strictly limiting the air that can _enter_ the bottom of the hive), having a screened bottom makes basically no difference in the colony's ability to maintain heat and/or scent. The amount of air-flow into or out of the hive is basically the same as with just the normal entrance being open, but the air that _does _enter is more evenly distributed. Moreover, if the entrance becomes blocked with dead bees or snow, ventilation is basically unaffected.

Screened bottoms make it possible to monitor varroa populations (something that Warre never had to do), perform powdered sugar varroa treatments, and monitor the bottom box so it is easy to know when the hive needs to be enlarged. They also work well in conjunction with beetle traps because they let light into the hive, which drives the beetles to the top where traps can be placed easily and then monitored and emptied easily by the beekeeper (also something Warre never had to do).

I think that guessing at what someone who died 60 years ago would or would not approve of these days is kinda silly and I am perfectly aware of what I am trying to do with these hives, thank you.


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## Buz Green

Beez 2010

I understand your thinking about the "chimney effect" but I think even the slightest breeze would cause a venturi effect and suck a lot of heat and scent out of the hive.


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## beez2010

Buz Green said:


> Beez 2010
> 
> I understand your thinking about the "chimney effect" but I think even the slightest breeze would cause a venturi effect and suck a lot of heat and scent out of the hive.


In order to work efficiently, as with a carburetor, a venturi has to have a particular design (round with one side cut out at angle). A square, flat, venturi would be extremely inefficient, almost a total failure in function. So do high winds cause some venturi effect? Probably, but most noticable only at the very bottom of the hive. The slightest breeze? No.

I actually am degreed in, and have worked extensively in this area of engineering, so I know a little about it.


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## Zonker

for whatever its worth ... I'm drawing plans for a talk I have to give. They're a little rough but I have a warre IPM floor plan in them. I used a 2x4 because it was quick and easy (and I'm really cheap).
http://www.box.net/shared/hkefz3qcic


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## Buz Green

beez2010 said:


> In order to work efficiently, as with a carburetor, a venturi has to have a particular design (round with one side cut out at angle). A square, flat, venturi would be extremely inefficient, almost a total failure in function. So do high winds cause some venturi effect? Probably, but most noticable only at the very bottom of the hive. The slightest breeze? No.
> 
> I actually am degreed in, and have worked extensively in this area of engineering, so I know a little about it.


I don't have any degrees but I have 64 years of life experience, 50 of which have been
in residential and commercial construction. "venturi effect" might not have been the correct term for what I was thinking but I do know for certain that I would not want to live in a home, built on stilts, with a floor of expanded wire mesh unless I lived in a subtropical area and I wouldn't want to pay the heating bills for one that was in a colder climate.


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## Kelbor

Hey, Thanks for the insights....I never intended to spark a somewhat heated debate! 

For the sake of science I may just run one of each. It will not be much of a sample size but if one fails or flourishes over the other for any of the discernible reasons discussed above it would be interesting. I also kinda like the prospect of peeking up into the hive with a mechanics mirror for a quick peek without popping the top (although the hive boxes do have sighting bungs that can be pried out for a peek). 

Any additional thoughts......keep them coming! Seems there really is no right or wrong technique - just tons of variation. Bees are tough!


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## beez2010

Buz Green said:


> I don't have any degrees but I have 64 years of life experience, 50 of which have been
> in residential and commercial construction. "venturi effect" might not have been the correct term for what I was thinking but I do know for certain that I would not want to live in a home, built on stilts, with a floor of expanded wire mesh unless I lived in a subtropical area and I wouldn't want to pay the heating bills for one that was in a colder climate.


Well, I'm sure you wouldn't leave your front door open all winter either. Should we block off our entrances for the whole winter, too? I thought we were talking about bees and hives, here.

Apples and oranges, man. Anything for an argument.

I was simply stating that when you said that breeze blowing under the hive would suck the heat and scent out of it, you didn't know what you were talking about, and then I backed up what I said with actual _science_, something that gets overlooked most of the time by people who want to over-simplify everything in this world.

Complex questions can't just be answered with a "Yep" or a "Nope".

Heat rises and bees don't cluster 2 inches from the floor in the middle of winter. No amount of ridiculous analogies will change that.


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## Buz Green

beez2010 said:


> Well, I'm sure you wouldn't leave your front door open all winter either. Should we block off our entrances for the whole winter, too? I thought we were talking about bees and hives, here.
> 
> Apples and oranges, man. Anything for an argument.
> 
> I was simply stating that when you said that breeze blowing under the hive would suck the heat and scent out of it, you didn't know what you were talking about, and then I backed up what I said with actual _science_, something that gets overlooked most of the time by people who want to over-simplify everything in this world.
> 
> Complex questions can't just be answered with a "Yep" or a "Nope".
> 
> Heat rises and bees don't cluster 2 inches from the floor in the middle of winter. No amount of ridiculous analogies will change that.


I don't understand how someone could argue the fact wind disturbance would affect a space with 4 walls and a roof and a porous bottom.
I won't comment further nor argue with someone with a sheepskin and obviously not a lick of common sense or manners.


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## Oldtimer

Even in Langstroths, I've noticed people returning to solid bottom boards. I tried screened bottom boards in mine, but now I'm back to solid bottom boards in nearly all of them, pretty much for the reasons stated by other posters in this thread.




beez2010 said:


> Screened bottoms make it possible to monitor varroa populations (something that Warre never had to do), perform powdered sugar varroa treatments.


This is a surprise!

Everything you've ever said that I've read, is that varroa are a non issue in a Warré. Now you appear to be recommending not only monitoring them but also treating for them.


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## gjd

If you don't insist on his exact entrance architecture, why can't you use a screen with a removable solid sheet a bit lower under that, as with many SBBs sold commercially for Langstroths? 

I've tried removing/inserting one in a 2-deep Langstroth for a few hours or a day and looking for changes in temp and humidity, and if there is any it's lost in the other springtime daily variability so far. I can't tell you what the bees think about scent.
Greg


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## Zonker

I think I'm going to put a screened bottom under them but close it except in the heat of the summer.


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