Too much moisture in the hive

Yesterday I when I pulled the drone frames out of the hives, I discovered the most populous hives were dripping wet under the cover. I had tried to prevent this by using upper entrances, but apparently the one-inch holes I installed were not big enough to keep the interior dry in spring.

Part of this problem is due to the weather; it has been rainy and cool for the last several weeks so it’s hard to keep anything dry. It’s also partly due to the populations in the hives—lots of bees mean lots of respiration and also lots of nectar collection. Everything, it seems, gives off moisture.

Moisture in the hive is not a good thing. Disease organisms, fungi, and molds thrive in moist environments and, in cold weather, water droplets can drip down on the bees and chill the brood. Proper ventilation is important for bee colonies year round. Bees can do really well in cold temperatures, but cold and wet is a different story.

I manage to keep my hives dry all winter with one lower and one upper entrance, but this time of year when the populations are huge and nights are still cold, it’s a bigger problem. So yesterday I removed the inner covers and replaced them with screen covers that have half-inch shims along the short ends. The shims prevent the outer cover from laying flat against the screen. The damp air can flow from the hive, up through the screen, and out the half-inch space on either side.

These screens greatly improve airflow but prevent insects—such as foreign bees or wasps—from coming in through the top.

After that was all done, I fed drone brood to the chickens—the ultimate in recycling! The nurse bees eat the pollen so they can secrete royal jelly and feed the larvae, and the chickens eat the larvae so they can lay the eggs which we can eat for breakfast—along with toast and honey, of course. What a system.


This 11-year-old Araucana hen thrives on drone brood.


Steven C

Do you use screened bottom boards? I do, and have never had a moisture problem. My hives sit at the edge of my lawn, and are shaded by trees a lot of the day. I even leave the SBB’s in over the winter (in Massachusetts).

Steven –


Hi Steve,

Yes, I should have mentioned that. I do use screened bottom boards and my hives are elevated so the air can easily flow up through the screens. Here in the Puget Sound region we are blessed with a rainy season that lasts nine months, October through June. It stops raining about the fourth of July and then we have zero, none, nada rain for three months, during which time everything dries to a crisp.

We probably don’t have much more total rain than you do in Massachusetts, put it just kinda rains all the time, enough so that mold and moss grow everywhere. We call it the “mold and mildew capital of the new world.”

Anyway, I think that is the main problem with keeping the hives dry, and it’s why I experiment a lot with screens and multiple openings. My bees have done well over the years, but I never open a hive without a bucket of rags so I can wipe down the inner cover.

I appreciate your comments, however. I’m glad to hear you use screened bottoms over winter. I try to encourage that but lots of people are afraid to.



“Drone brood”? What’s that? Drone’s are male bees and brood are the larvae, right? So is “drone brood” larvae that will become drones? I get why the hens want them, :) but why don’t you want them?


Hi Anneke,

Thanks for writing. You are right, drone brood is brood that will grow into drones. As for why I don’t want them, read about reducing varroa mites by drone trapping Drone brood produces many more mites than worker brood. It’s nothing personal.


Could you use a moisture board in the hive to help with the excess moisture?



What’s a moisture board? I’m clueless.


I am having such terrible issues with the moisture and mold, too. I have been propping open my lid with a stick to get some air flow, which is helping a little bit but provides no protection from any foreign marauding creatures. I already have a screened bottom board and an elevated hive. I go back and forth about whether I should get a screened inner cover, too.

If this rain doesn’t end soon………. I don’t know! Everyone’s going a little bit crazy.


I have one hive in particular that is just dripping inside. I have a screened bottom board and a screened inner cover. I was wiping out the lid every other day, then I decided I’d split the hive in two. I checked it yesterday after it was split for a week, and now both halves are dripping! What’s going on with these guys, I have no clue. The rest of my hives are not a problem. Weird.


I’ve been having the same issue. Mainly seeing mold on both lids, everything else looks ok. Do you think I should clean it of some how? I’ve cleaned 1 box lid using a wire brush but I know that doesn’t get rid of the mold completely. Any recommendations?



Vinegar helps retard the growth somewhat. Just take a vinegar soaked rag and rub down the inner surface of the lids. It will grow back eventually, but it’s quick, non-toxic, readily available, and works reasonably well.


HI Rusty,

I have a suggestion that may help with with dripping lids although I know you are now recommending the use of wood shavings in a quilt box and a gabled roof. If the lid could be built so that it had about 1″ of slope from one side to the other and on the low end, the apron board would have a 1/4″ gap below the lid. Line the underside of the lid with aluminum flashing, extending it thru and maintaining the slot.
The moisture should condense on the cold metal and roll down the slope and out of the hive. A cleat could be added under the slot to divert drips off the side of the box and screening could be attached to prevent invasion.
Freeze up? Not sure, but I didn’t experience any problems. At worst, it should stop dripping in the center of the hive and move it to the side where I assume it would do less damage.
And by the way, if drips to the sides would be less damaging, why not use an inner cover with the holes on the sides rather than in the center? You were the one who said something about there not being any dumb questions.
Thanks Rusty



It sounds like a reasonable idea to me. Have you tried this or are you going to? Could be interesting.


I tried it winter of ’11-’12 with a gabled roof over a quilt box with a 3″ thick wool insert; 2″ vents in eaves. The blanket stayed dry.
I will try the slant roof this winter coming, tho I’ve switched to using a piece of 4″ Styrofoam for tops.


Hi Rusty,

Eating my words again. Upon further reflection after reading your post, “SHOULD MY HIVE TILT FORWARD”, I don’t think a sloped inner metal lid would work. The moisture would freeze and form icicles and drip down upon melting. Another wrong idea.


It’s nice to read information and experience on moisture in a beehive when the beekeeper is located in the Pacific Northwest. It is such a different experience from other areas and I’m having much trouble. Here it is mid October and I already have a hive that is molding and smells sour. I’m wanting to try a wool cloth on top with a vent slot. I’m glad to have found your website now and I hope to get some great advice. Screening the top board is something I never thought to do (*slaps head*). Thank you for a great blog.



You are right. Ventilation and moisture control around here is the number one priority, both for them and for us.


After thinking about those screened top boards…are you just adding a screen over the little hole in the inner cover? Or are you adding a whole sheet of screen with just a wooden frame around it? How much top ventilation do you do? All of our hives have very little stores right now. Was this year a poor season for honey stores or have I missed something?



A photo of a screened inner cover is here. For ventilation, I use a screened inner cover and a screened bottom board. I don’t know where you are, so I can’t say if it was a poor season.


Thanks for directing me to the post. Thanks exactly what I was looking for. I live just outside the Portland Metro area. I was surprised when my six hives all have basically no stores. So I am making candy boards already.

Peter Bathurst

I use a 4 inch quilt filled with cedar shavings with a pitched vented roof and have never had a moisture problem. The shavings never get wet. Instead of drilling vent holes, you could save time by just adding shims under the cover.



That makes sense. Thanks!