Screened vs Solid Bottom Boards: Which Should You Buy?

Buy screened. In nearly every US climate a screened bottom board with a removable insert is the better floor, because it gives you summer ventilation, a monitoring surface, and beetle drop-out during the eight months that matter, and then becomes a solid floor for the four months that do not. The only readers we would push toward a permanently solid board are those in the coldest, windiest sites who will never pull the insert anyway, and even they usually benefit from having the option.

The correct mental model: you are not buying a bottom board type, you are buying a bottom board plus an operating schedule. Insert out in spring, insert in for late fall, tray in whenever you want a mite count. That is the whole system, and it costs $36.49 with our top pick.

Note the row that decides the argument: screened with the insert in is functionally a solid board. Solid boards cannot become screened boards. That asymmetry is the entire recommendation.

Screened bottom boards were sold for years on the promise that mites which fall through the mesh cannot climb back, so the colony sheds its varroa load over time. The premise is true. The conclusion is not, because the share of the mite population that falls on its own in any given period is small relative to the share reproducing under cappings, and removing a small fraction of a fast-growing population does not change its trajectory.

Current guidance treats screened floors as a monitoring aid, not a control. The Honey Bee Health Coalition Varroa management materials and extension bee-health programs both build their recommendations around measured infestation levels and registered treatments, with an action threshold commonly given as roughly 2 to 3 mites per 100 bees depending on the season. Varroa destructor reproduces inside sealed brood cells, which is precisely where a floor cannot reach it.

What screened floors genuinely give you is a place to put a sticky board. That is not nothing: it is the cheapest, least invasive way to watch a mite population between washes and to check whether a treatment did anything. Our mite monitoring roundup covers the washes and shakers that set the actual threshold, and the treatment timing guide covers what to do about the number.

A sticky board is a sheet that slides into the tray slot under the screen, coated with something mites stick to: petroleum jelly, cooking spray on a corrugated sheet, or a purpose-made adhesive board. Everything that falls out of the colony lands on it, which includes wax cappings, pollen, dead brood, beetles, and mites.

The routine that works: slide the board in, leave it 24 or 72 hours, pull it, and count mites against a grid. Divide by days to get a mites-per-day drop. What that number is good for is trend and treatment verification, comparing this week to last week, or the week after a treatment to the week before it. What it is not good for is setting a treatment decision on its own, because natural drop varies with brood cycle, colony size, and weather. Use an alcohol wash or sugar roll for that call.

Two practical notes. Ants will find a sticky board and so will beetles, so pull it on schedule instead of leaving it in for a fortnight. And in a screened hive with no insert, the board sits below the screen where bees cannot reach it, which is exactly the point: the bees do not clean it and the count stays honest.

A colony in a July heat wave spends a substantial share of its labor force on climate control, fanning at the entrance and evaporating water inside the hive to keep the brood nest near 95F. Every bee doing that is a bee not foraging. Opening the floor gives the colony a chimney: air enters low, exits at the top, and the fanning workload drops.

The second summer benefit is nectar curing. Ripening honey means driving moisture out of the nectar until it sits below roughly 18.6 percent water, and moving air through the hive helps. Beekeepers in the South and Southwest often report supers curing faster over screened floors, which is consistent with the physics even if nobody has handed us a controlled trial. Our hot climate guide covers the rest of the summer setup, including shade and water.

If you keep bees where summer highs regularly clear 95F, this section alone settles the question. Pull the insert in April, leave the floor open all summer, and let the colony work on nectar instead of air conditioning.

The small hive beetle is a scavenger that entered the US in the 1990s and is now endemic across the Southeast and much of the country. Adults hide in cracks the bees cannot reach, larvae tunnel through comb and slime the honey, and a heavily infested hive can be ruined in days. Bees defend by corralling beetles into propolis prisons, which works until the colony gets weak.

Screened floors help in two ways. Beetles knocked off comb during an inspection fall through the mesh instead of scuttling back up, and the tray slot becomes a place to run oil traps that beetles fall into and drown. Neither is a complete answer, and neither replaces the in-hive traps that do the real work. The complete picture, including the corrugated and blaster-style traps that fit between frames, is in our small hive beetle guide.

The important interaction is with colony strength: beetles overwhelm weak colonies and lose to strong ones. Do not run more boxes than the bees can patrol, keep the entrance reduced on a small colony, and never leave supers of wet comb sitting where beetles can work them.

This is the solid board's best argument and it deserves a fair hearing. A winter cluster generates heat and holds it in a ball; a hole in the floor beneath that ball lets cold air move through continuously, and in a windy site the effect is real. Beekeepers who have left screened floors wide open through a northern winter and lost colonies are not imagining things.

The fix is the insert, not a different board. In late fall the corrugated or plastic tray slides into the slot, and from the colony's point of view the floor is now solid. Nothing else about the hive changes. Come spring you pull it out again. That is the whole procedure, it takes seconds, and it means the screened board is strictly better than a solid one because it has a setting a solid board does not.

Two supporting jobs matter more than the floor either way. Reduce the entrance so wind does not blow straight through the box, and give the hive a way to vent moisture at the top, an upper entrance, a shim, or a quilt box. Our winterizing walkthrough and the winter season guide lay out the order of operations.

Healthy colonies survive cold. What they struggle with is condensation: a cluster respiring inside a sealed box drives warm wet air upward, and when it hits a cold inner cover it condenses and rains back down on the bees. Cold wet bees die where cold dry bees would not. This is the single most useful thing to understand about overwintering, and it reframes the bottom board argument.

A screened floor with the insert out lets some of that moisture leave downward, but it also lets heat leave, which is why we do not recommend running open floors in a northern winter. The better arrangement is insert in below, ventilation open above, so moist air exits at the top where it belongs. A quilt box, an absorbent shim, or an upper entrance does more for winter survival than any bottom board configuration.

National loss surveys from the Bee Informed Partnership have put annual US colony losses in the range of 40 to 50 percent in recent years, and the causes they point at are varroa, starvation, and queen failure rather than floor design. Fix those three first. The bottom board is a comfort variable, not a survival variable.

Solid boards are not stupid, and here is their real constituency. If your apiary sits on an exposed ridge in a place with long, hard, windy winters, and you know from experience that you will not remember to manage an insert, a solid floor removes a variable. If you run hives on pallets that get moved by truck, solid floors have fewer parts to lose. If beetles are not a problem in your region and you never run drop counts because you always do alcohol washes, the screen earns you less.

There is also a small brood-nest argument: some beekeepers believe an open floor makes early spring buildup slower because the colony fights a colder cavity while it is trying to expand brood. The evidence is thin and the effect, if it exists, is handled by putting the insert in until the weather turns. Which is, once again, an argument for owning a board that can do both.

What we will not accept is the claim that solid boards are better because screened boards let mites back in. They do not. The screen is a one-way floor either way.

The bottom board is the base of a small stack of components that all interact. A slatted rack sits between the floor and the bottom brood box, giving bees a place to hang in hot weather, reducing congestion at the entrance, and buffering the brood nest from direct drafts. Beekeepers who add one rarely go back. An entrance reducer narrows the opening so a small colony can defend it, which matters most in the first weeks after installation and again during fall robbing season.

The order from the ground up is: stand, bottom board, optional slatted rack, entrance reducer at the opening, then brood boxes. Get the hive off the soil first, because a bottom board sitting on dirt will rot no matter what it is coated with. Our stands guide covers the base, and the reducers and robbing screens roundup covers the doorway.

Pick a screened bottom board if: you live anywhere with real summer heat; you want to run sticky board mite counts; small hive beetles exist in your county; you are willing to slide an insert in each fall; or you simply want one floor that covers every situation. Start with the BeeCastle Screened Bottom Board at $36.49, or the Apimaye Premium Screened Bottom Board at $72.00 if you want the last floor you will buy.

Pick a solid bottom board if: your site is genuinely brutal in winter and you will not manage an insert; you move hives on pallets and want fewer loose parts; or you already own solid boards and there is no reason to spend money changing them. A solid floor is a fine floor. It is just a floor with one setting.

Either way: get the hive on a stand, reduce the entrance for small or wintering colonies, and vent at the top in winter. Those three do more than the choice on this page.

For a first hive: the BeeCastle Screened Bottom Board at $36.49, on a stand, with the insert stored in the shed until October. That is the whole decision, and it is under forty dollars.

For a second hive or a spare: the witbee Screened Bottom Board at $36.33, kept with a spare deep and a set of frames so a swarm call never catches you short. For a wet or shaded yard: the Honey Lake Metal Screened Bottom Board at $36.99 for the metal mesh. And for anyone running insulated equipment or tired of replacing rotted floors, the Apimaye board at $72.00 is the end of that conversation.

Then go do the thing the floor cannot do: monitor mites with a wash, treat on a threshold, and feed a light colony going into fall. The full field of floors is ranked in our bottom boards guide, and the seasonal jobs are laid out in the fall guide.