Screened inner covers can give your hive a lot of good ventilation. They are used in place of regular inner covers and are designed the hold the telescoping cover up on two ends (or two sides) so that air can flow from the hive and out from under the telescoping cover. The screen is tacked down with narrow strips of wood that are just thick enough to provide some bee space between the top bars and the screen.
You can buy screened inner covers from some of the bee supply houses, but they are also easy to make. I bought long pieces of standard 1 x 2-inch lumber, and used the 2-inch dimension to provide the height necessary to elevate the cover, and I used the 1-inch dimension for the front and back.
The way I cut my pieces, the ventilation air goes out the front and back of the hive. You can also reverse the pieces so the ventilation air goes out the sides, the way the commercial ones do. Either way works, although you will get more air flow if the air goes out the sides, which are longer than the width. However, if your hives are close together, having the air go out the front and back may be best.
- First I cut all the wood to the proper length. I had help cutting the strips, which were ripped from a standard 1 x 4.
- Then I cut out a notch on each end of the long pieces where the corners will join together.
- I used a square to assure right angles, then I pre-drilled the holes with a countersink, so the screws could be recessed.
- If you are going to paint, this is an easy time to do it, but painting is not necessary.
- I cut a piece of #8 hardware cloth to size, stapled it in place, and then stapled the wooden slats over the edge. The cloth needs to be stretched tight to limit the amount of sag in the center. The wooden slats give you a nice clean edge and they also provide bee space.
- When you install the cover, remember that the screen side goes down.
- Center your telescoping cover over the screen so there is room for air to travel out each end (or side).
Note: for a complete set of plans, see Screened Inner Cover
Thank You Rusty for your e-mails and your hard work. I enjoy your writings very much, Ted
Please excuse my ignorance, but what is a telescoping cover?
Well I did the sensible thing second instead of first. I searched it on your site and found a very nice explanation. Of course now you have to read two comments but at least your reply will not have to be as long.
Or maybe I won’t reply at all!
Hi! Thanks for the great post. A couple of questions if you have the time:
How has this worked out for you?
How many seasons have used it?
Any observations on yield? Behavior?
Do the bees attempt to propolise it?
Thanks and regards.
I’ve been using screened inner covers for five or six years. I would never again keep bees without them. Both honey production and brood production seem to improve with better ventilation. Propolis has never been a problem; sometimes there is a bit of burr comb which can be removed with a heat gun or air compressor.
How high should the inner cover actually “lift” the outer cover? Should I be able to see a gap in it?
Mine lifts about 3/4 of an inch. You can see from the photos in this post.
Mine lifts about 3/4 of an inch. You can see from the photos in this post.
Well, I have an, err, “custom” telescoping cover. I was just wondering if there should be a visible gap on the underside of the tip cover. Thanks.
Sorry, Robert, I don’t understand what you are asking. I confess to being dense at times . . .
I am pretty sure it’s my communication skills lol Thanks for your patience.
Ok let’s see. I bought hives from the Mann-Lake distributor. They came with a top that was flush on the sides. I decided I wanted a telescoping cover, so I added sides to it.
My question is, for a screened inner cover to be effective, does it have to raise the telescoping cover to the point that there is a gap between the bottom of the telescoping cover and the vent sides of the inner cover. I will try to email you a picture to see if that helps.
Screened inner covers are usually shimmed on two sides to hold the telescoping cover far enough away so that air can flow over the other two side. If air can’t flow, then it can’t ventilate. The openings can be under the overhang of the telescoping cover as long as air can move freely from the inside of the hive to the outside.
Great post. I’m in E. WA and am concerned about next week’s weather as we’re supposed to be over 100. One question…where in the world do you find #8 wire cloth? That stuff seems to be as scarce as hen’s teeth, but everyone seems to have it for beekeeping projects. I can’t find it.
So weird. I haven’t been in eastern Washington in ages, but I’m heading out there next week to meet with some bee people at WSU in Prosser. Perfect timing for the heat wave of the decade. You can buy #8 hardware cloth (1/8th-inch squares) from Amazon.com.
In a pinch (in case you can’t get it before the heat wave) you can use regular insect screening from your Home Depot or whatever. It will keep your bees cool, but it won’t last like hardware cloth.
Yeah, need will eventually chew through the insect screen.
Thanks for sharing knowledge 🙂
With screened inner covers, do you leave them in all winter (I am in southeast Iowa) or should I take them out & put the regular inner cover on till spring?
I also have screened bottom boards, which I have read that is good to leave in over winter to help reduce moisture.
I use the screened inner covers in the spring, summer, and early fall, and then I replace them with them with moisture quilts for the winter. I seldom use the standard inner covers.
I leave the screened bottom boards open all year except when it stays in the low 20s for more than a few days. Then I slip the removable drawers back in. With a really populous hive it doesn’t matter much in my climate, but for smaller colonies I like to give them some help.
Thanks for your reply. I am gonna have to Google moisture quilt & read up on them. First I have heard of them. Which is not a surprise being my first year with bees.
How to make a moisture quilt
Hi Rusty, I installed the screened inner cover and immediately the bees started building burr comb which was very troublesome. Determined to have the ventilation I came up with an idea/experiment that has turned out excellent, so I wanted to share.
I took a regular inner cover with an entrance and drilled one inch holes all over it spaced about 1/2 to 3/4 inches apart as I didn’t want to weaken the cover too much. This turned out great.
I then turned the drilled inner cover upside down (wrong side up) and put the screened inner cover on top. The bees now have an upper entrance and they do not build any burr comb on either side of my contraption.
The bees have propolized the two pieces together and I can take this system off in one piece. When I take them off for winter and install my quilt board, I am going to nail the pieces together making the setup permanently into one piece because they worked so well.
I also have an idea for my quilt board I would like to share. I am placing a wood bound queen excluder on the upper brood chamber and placing the vented super on it. I have burlap, double layer, to place inside on top of the queen excluder and then the wood shavings on top of the burlap. Without attaching canvas or burlap directly to the vented super, I can lift the burlap and wood shavings out and replace with newspaper and clumped up sugar if I need to feed .
I hope this helps someone to make beekeeping a little easier while maintaining proper hive integrity.
Regards to all.
Thank you for your information. We had our first warm day 2 days ago and our new nuc was bearding. We have forecast temperatures of 41 and 42 for Christmas/Boxing Day, so off to Murray Bridge yesterday for materials. We have made a heat screen, similar to yours for each hive and put them on Friday when the nights and days warm up again.
Merry Christmas 2016
They really do help to keep the bees cool. You will like them. Merry Christmas to you, too!
Do you use screened inner covers and bottom boards even in the winter? This is my first time on any blog so hope I’m typing in the right place.
You are typing in the right place.
If you mean me personally, I leave the screened bottom boards open all winter, but I take off the screened inner covers in the fall. I just put them back on this week. What works best will depend on your local climate.
I live in a sub tropical area, so year round will probably be OK. It only gets down to about 15 celsius in the early morning during the cold season.
Rusty – Do you use queen excluders? If not, do you have any problems with the queen putting brood in the supers? Last summer I added shims between supers. Got brood in the supers.
For many years I did, then for a few years I didn’t, now I do again. It depends on your tolerance for brood in the honey supers. Without an excluder you always run that chance.
Rusty, can you tell me the thickness of the pieces ripped from the 1×4″? Are they 3/8″ or less (understanding of course the idea is leaving just enough bee space).
Thanks for the “how to” (was just what the doctor ordered) and in advance for the info.
Mine are 3/16-inch. The real bee space is provided by the top bars, which are recessed from the top of the box.
Thank you so very much!
I’m a newbee and this site has been a blessing! Can you provide the measurements for the wood for this screened cover? I do way better with numbers than pictures 🙂
Is the screen cover contraption smaller than the telescoping lid thus nesting as it were or does the lid rest on the cover edges? Sorry to be so dumb…
I keep forgetting to do this. I have to take one off a hive and measure. Truthfully, it doesn’t matter. You can size them anyway you want.
Thanks for all your great information. I come across your post quite often when I am researching things. 🙂
I have several feral swarms and decided to feed them so they can build up comb. I just ordered some Mann Lake top feeders and was wondering whether to use my screened inner covers on them when I came across this discussion thread. I suppose I will try putting them on top of the feeders, but I am wondering about the potential impact of my other nearby hives smelling the syrup? Will bees collect on top of the screens and possibly agitate the bees by having foreign bees inside there?
I’m not clear. As you saying you’re going to cover your hive-top feeder and make it into an inside feeder? Or what you’re buying goes inside to start with? In any case, one purpose of the screen is to keep other bees from going in. If they are busy sniffing the top screen, they may not try to go in the main entrance.
I’m planning to go to horizontal long hive and will be switching 5 existing Langs to those new hives. The only thing I can think of in light of all the above info of this subject is to try to locate the new long lang 3 ft from the existing hive to make the switch and wait a period of time then resume with the method you have laid out. Will that work or is there a better way?
I’m sorry, but I don’t understand your question. Did you mean to attach it here on “How to make a screened inner cover?” I don’t know what method you are referring to.
Thanks for the info on the inner cover. I have a ventilation problem and I’m thinking of building one. However, I like the idea of the upper entrance to ease access to the honey supers. With this screened inner cover, there is no upper entrance since the screen is against the bottom super? Is there any way around that?
I’m not sure what you mean by “the screen is against the bottom super.” In fact, the screen lays just above the top of the top super. I always use a screened inner cover and my upper entrances are drilled through my honey supers.
Alternatively, you could place an Imirie shim, including entrance, above the top super and put the screened inner cover above that. I’ve done it that way many times in the past.
Sorry, Yes I meant the top honey super. Thanks, I understand your honey super has an entrance drilled through the side.
Different topic. Is it safe to assume that most all the bees returning to the hive are carrying nectar if they’re not carrying pollen?
No. A lot will be carrying water. Some will be carrying propolis. A few carry both nectar and pollen at the same time.
I’m near Olympia WA, thanks for the great info! I recently made some screened boards for jar feeders, which use a standard medium body, then regular inner and outer cover. I as considering building a medium body with 4 inch screened holes on the sides. Would that be too much ventilation?
Depends on the season. Four-inch holes would be fine for summer but might be a bit much for cold weather.
Hi Rusty (cool name btw),
Thanks for your response. I planned on only using jar feeders, and the afore mentioned feeder boxes during spring, summer and fall as needed. Something in your response made me question the larger holes. Would smaller diameter holes regulate heat better, ie. not too much, not too little? In your opinion, is there an optimum?
No, I just thought 4-inch holes were too big if the feeders were used in winter. They would be fine in milder weather. Smaller holes might keep out the rain more effectively, though, depending on where you put them.
Ah, the rain. How could I forget? (Really, I’m in the PNW after all.) Now I’m thinking two inch holes with awnings lol.
With 4″ holes drilled into your supers, aren’t you afraid the holes are too big for the bees to defend?
You lost me. I don’t know what you’re referring to. I don’t have 4″ holes anywhere.
Hi Rusty! I might have just missed it in your description, but how thick are the shims (front or sides) used to allow air to flow out between the inner cover and the telescoping cover? Beeing a beginner, I made some by covering an imirie shim with mesh, but didn’t include shims which I guess I should do now! Thanks! Gary Thomas
There is no rule for this. You want air to flow past the shim but you don’t want to encourage robbers or wasps.