Making and Using a Ventilator Rim

THE FOLLOWING WAS LAST UPDATED ON AUGUST 22, 2011.

Well, not really making a ventilator rim. I already made it and it looks like this:

Like the name implies, it provides ventilation for the hive. And as far as I know, it’s good to have on the hive any time of the year, though for the winter we might stick with our insulated inner hive covers. They worked out well for us this past winter.

I think the rim is also called an eke, a shim and something else I can’t remember at the moment. But ventilator rim is easier to understand than any of those, so that’s what I’m calling it. And this is what it looks like on a summertime hive:

And this is what it looks like when you poke your head down inside:

I have two ventilator rims, one built by a fellow beekeeper who has real carpentry tools and knows how to build stuff (his is the one in the second photo) and another built by me (the one in the first photo). Mine is easy to spot because it has sloppy, smaller uneven holes.

The rim is three inches high, once inch thick, and the pieces of wood are screwed together to match the dimensions of a standard Langstroth super. The ventilator rim I made has holes drilled on every side except the side facing the front — three holes on the wide sides, two on the back. A good idea to help minimize wind-driven rain from getting inside is to drill the holes at an angle pointing downwards from the inside out. That way whatever rain does collect on the sides of the holes will pour outside the hive immediately, if that makes any sense. Don’t worry about it if it doesn’t. I also stapled some screen over the holes on the inside of the rim.

Wind blows through the holes but wasps and other predatory insects can’t get in. As you can see from the second photo, I put an extra medium super over the rim because when I put a telescoping top cover directly over the ventilator rim, it covers over most of the holes on the rim. The extra space from the medium super along with the wind blowing through makes it easier for the bees to evaporate nectar into honey. Heat and moisture building up inside the hive can readily escape through the hole in the inner cover, and is then blown out through the ventilator holes. The bees don’t have to beat their wings so much and work as hard to create an evaporating current inside the hive. That means less resources spent on creating honey, which means quicker honey production and more of it. A win-win situation for everybody. The extra ventilation also makes it easier for the bees to regulate the temperature of the hive for brood rearing. So it’s all good. And in the winter, the ventilator rim can help prevent condensation from building up in the hive, which makes it a triple whammy of good news (though, again, we might stick with our insulated inner hive covers for now because we know they work for our particular wet Newfoundland winters).

Our hives have been slow to start building in their honey supers this summer, but it’s a different story since we installed the ventilator rims. We can see the bees crowding around the inner cover hole above the honey supers all the time now, which is probably a good sign that the bees are working the honey supers. There could be, and probably are, other factors involved, but providing the hives with better ventilation through the ventilator rims probably doesn’t hurt.

Leave a comment if you want to know exactly what it took to make the ventilator rims. But I can tell you it was pretty cheap and easy. Otherwise, I’d probably never bother with it.

UPDATE (August 06/11): I’ve been told since I got into beekeeping that proper ventilation is key to colony health and honey production. I’m curious to see if these ventilator rims make a difference. They’re much like the basic ventilated hive design. I suspect the effect of the ventilator rim is exactly the same, only cheaper to make and easier to use. Already it seems the bees are building into the honey supers faster, but that could be coincidence. Either way, I’m excited about anything that might help our bees thrive on this cold rock in the middle of the North Atlantic. At least I don’t think it’s harming them.

UPDATE (August 08/11): Check out this comment from Rusty for a detailed explanation of hive ventilation (reproduced in a full post on her website: Physics for beekeepers: How does ventilation increase honey production?).

UPDATE (August 09/11): Check out Improving Langstroth Honey Bee Hive Ventilation with The Mud Songs Ventilator Rim™ for detailed instructions on how to make a new and improved version of this ventilator rim. (It’s still cheap and easy to make. And of course I’m joking about it being a trademarked invention.)

UPDATE (August 22/11): Click on the newly-created Ventilation category. I’ve always read about how important ventilation is to the health of a hive (it also speeds up honey production), but until now I haven’t seen the difference it can make. I’m only going on what I’ve seen in one hive since I added a ventilator rim and a screened inner cover, but so far it’s looking good.

3 thoughts on “Making and Using a Ventilator Rim

  1. The ventilator rim creates an airspace above the top bars and below the cover, correct?

    Do the bees ever fill this space with wax comb during a heavy nectar flow? I would imagine them filling it with comb and honey during our springtime wildflower and citrus flows here in Southern California . . .

  2. “The ventilator rim creates an airspace above the top bars and below the cover, correct?”

    It creates some air space above the inner cover and below the top cover, not technically inside the hive itself. At least that’s my understanding of it. The airflow between the ventilator holes pulls the moisture from the hive. Again, at least that’s my understanding of it.

    “Do the bees ever fill this space with wax comb during a heavy nectar flow? I would imagine them filling it with comb and honey during our springtime wildflower and citrus flows here in Southern California…”

    Good question. My answer is I don’t know because this is my first time using it. I have seen photos of bees building comb in empty supers above inner covers, but usually when packages are installed and the queen isn’t happy with the brood box for some reason.

    Ask Rusty. She might know.

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