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So, there was a problem at the house, and I thought I’d have a simple solution: I wanted to remove my bee-infested front porch railings and glam up the entrance to the house. Simple. As it goes with some projects, it didn’t stay that way.
Removing the railing and wrapping the posts in cedar had been the plan for years, and for a long time, I’d noticed that carpenter bees would fly in and out of the railing. They made a huge mess of sawdust by drilling into the old wood, and I had grown sick of ignoring it (my friend Brittany from Pretty Handy Girl was practically giddy when she saw me ripping it out on my Instagram… gotta love that DIY support, right?). It finally gave me a chance to actually see what kind of damage they did, but I was also fascinated by how nearly perfect the holes were.
Upon removing the railings, I got a message from a follower who asked me what I’d planned on doing to re-house the bees. “They’re great pollinators for your garden! You should try to give them a new home if you can.” It’s probably no shock to you, but I actually hadn’t given it any thought. And once I did, I thought no biggie, I could take some scrap wood, build one of those cute little bee hotels I’d seen at garden centers, and call it a day, feeling good that I had a sufficient answer that didn’t involve bee murder and bonus, free plans for anyone else who wanted to build one. Win-win!
And then. And then. I looked up some quick info on mason bees (I swear, just to get a few pointers because I like being informative), and there was such a rabbit hole, I knew this was no longer a short thing for me. This may seem so silly at first, but I’ve got SUCH a long post for you today. I’m nerding out today with the #beefacts. As it turns out, there’s a lot more to building a good bee house, and some of it may surprise you! This is one of those posts where I warn you to take your coffee break and settle in. We’ve got knowledge to drop.
(if you don’t want to nerd out with me and just want the plans, scroll down to that section or click on the table of contents below to jump down)
In This Post
- Why most bee hotels you can buy suck
- Why solitary bees are cool
- Why bee houses should be more spaced out
- Why bee houses need to be kept clean
- How to prevent invasive species
- Where to place bee houses for better results
- Why color is important
- My DIY “Better Bee House” video and tutorial
- Where you can grab the free plans
How to Build a Better Bee House
RESEARCH IS KEY! It might sound odd at first, but there are actually good rules of thumb to build the best bee hotel possible. After reading a number of articles and studies on the impact of bee houses, I used a few notes for making my setup to keep the native bees healthy and as close to their natural habits as possible.
The main message I got from reading up on “why bee hotels can be problematic” is this: we make a lot of assumptions based on our own aesthetics vs. what a bee might actually need, and most manufactured bee hotels are created for a variety of species that may not even be native to your region. I’m breaking it down even further below!
Why Bees Need Different Habitats
One thing about my rabbit hole researching made clear: not all bees are the same. While I definitely have carpenter bees who drill holes and make a mess, I may have mason bees as well (which I assumed were the same, but some identifying characteristics differentiate the two).
- Mason and carpenter bees are solitary bee species, meaning they aren’t like honeybees (social bees) that cluster together with different jobs and a queen. Instead, they do all the work themselves (much like our DIY community!).
- Mason bees are excellent pollinators. Honeybees get a lot of credit for the work they do, but since the humble mason bee gathers pollen all over its body as it hovers from flower to flower (she’s kind of a messy bench, which I can appreciate), can pollinate 95% of the flowers they visit versus the honeybee’s 5%, which only collects pollen on their back legs.
- Solitary bees are very docile and don’t sting (some females do, but very rarely). Sure, it’s annoying when a carpenter bee drills a hole into the side of your house, but not nearly as annoying as a bee sting.
- Solitary bees make their nests and pollinate in a much smaller square footage (300 feet) versus honeybees (around 2 miles), so you can put up bee houses in your garden and will likely get excellent results.
- Bees recognize faces (so don’t swat at them!).
- Carpenter bees drill holes, while mason bees look for existing ones. Mason bees are also a little smaller and fuzzy, while carpenter bees are the huge whoppers with a smooth abdomen that make people on my Instagram freak out. 🙃
- Even though carpenter bees drill holes, they can also be lazy, meaning providing an existing bee house may entice them to avoid drilling into your porch and deck.
Not all bee species are the same, so it makes sense that they don’t all like exactly the same environment for their eggs. Factors to consider:
- Depth of holes: some hole depths tend to produce males, and some hole depths produce more females. So, it would serve to vary hole depths rather than make them uniform. In general, 6-8 inches deep produces best results (I measured the ones in my railing and they were a little shorter, so I kept this consistent for my bee house, but future ones I build will be deeper)
- Lined/unlined: again, not all bee species have the same habitat, so sometimes lining holes with little cardboard tubes helps attract them, and sometimes it doesn’t. The best thing to do is to research what types of bees are native to your local area, and make sure the houses you build are friendly to that species.
- Hole diameter: some species bore smaller holes than others. This was an easy one for me to research since I had samples from my porch railing to measure! Most online research says holes should be 5/16″ in diameter, but mine were slightly larger (I assume possibly from repeated use).
Keeping it Clean
One HUGE tip I picked up from the articles I read was that bee hotels need to be maintained every year or two. It makes sense if you think about it — would you enjoy staying in a hotel that never changes the sheets?
- Cycle out the wood holes every year or two. This will both help prevent the buildup of mold and parasitic pollen mites that feed on bee eggs and larvae.
- Bee houses should have replaceable or cleanable components. For example, you can make sections using premade tubes like these paper straws.
- Since I was going with wood (to match closer to a native environment), I factored disposability into the design. The wood structure that holds each drilled section would be made to be more permanent, but the block itself would be easy to remove. Every two years, I’ll create a new one to fit with new drilled holes. This also allows me to not have to find solutions for harvesting cocoons in the winter (my eagerness to maintain this side project only goes so far).
Preventing Non-Native Species and Predators
- Pick an identity. Bee hotels tend to have a huge variety of cardboard tubes, drilled holes, sticks, etc. all mixed up together. That isn’t really ideal. Instead, make smaller bee houses that are dedicated to just a few types of holes.
- Keep bee hotels SMALL. A common complaint I saw from experts is that many manufactured bee hotels are simply way too large. Solitary bee species space themselves out from each other. So, the big bee condo you may see in stores will actually overcrowd what would normally occur in nature! They also invite wasps to lay eggs and other creatures, which might actually prevent native bees from moving in. Keeping the houses small and spacing them out also prevents disease from hitting one cluster and spreading to the rest, which could wipe them all out in a single season (same for predators… clustering turns the hotel into an insect buffet).
- Avoid bamboo and plastic. It doesn’t allow moisture to dissipate and humidity invites larvae/pupae to rot.
- Avoid glued-in nesting. For similar reasons as above, don’t buy houses that have blocks and reeds glued in. It doesn’t allow for you to add fresh materials in the spring and invites mites that kill off bee larvae.
- Add an overhang. If you’re building a bee house, provide an overhang and a back to the bee house so there’s protection from rain. While the bee house I made has a small overhang, future ones I build will have even more (going back to the hole depth issue, I’m planning on making a few with much deeper holes too based on the scrap materials I accumulate).
- Solitary bees may nest in the same spots year after year. They are communal rather than social, which means they build nests close to one another even though they don’t cluster together (like the carpenter bees that bore holes in my railing, for example — holes were made on the underside in equal distances apart and used every year).
- Don’t hang it from a string. Housing swaying in the wind may knock eggs/larvae loose off of pollen balls.
- Place bee houses with exposure to morning sun to keep the bee house warm. It’s also good to face them in slightly different directions from each other (I cannot remember why I wrote that note, so I’ll have to find the source again).
Did you know bees can see color — but not the same color spectrum that we do? In fact, bees apparently see red as black and may perceive it as a threat, so they may steer clear of bee houses painted in red/orange tones (or see them as all the same and get confused). For these same reasons, avoid dark colors. Entomologists instead recommend colors like blue and purple.
Color also helps some bees recognize where to return and which holes they have laid eggs in. This house will be blue, but I plan to differentiate other bee houses I make with a variety of colors.
DIY Carpenter Bee House — Free Plans
Using all of the above research, I nixed my original plan of building a larger bee house, and will instead build several smaller ones. I constructed most of these houses out of scrap lumber, so they aren’t all going to look alike. I also plan to make them different colors so bees can better recognize the locations of their nests (I’ll share photos of the others in future updates to this post). And since I’m building a few, why not share some free plans while I’m at it, right? I’ve included a quick video and tutorial below, courtesy of Krylon (they sponsored this project on my Instagram, so I wanted to disclose that for the sake of transparency!). You can probably already gather plenty of info on that alone to make your own bee houses, but I’m adding plans too!
And, of course, I know I have to add: I wrote all of this clearly demonstrating that I’m not an entomologist or any kind of bee expert. I relied on both notes from the internet and observations from what I found in my own porch railing to make decisions on depth, hole size, etc. I chose spray paint to protect the housing from the elements while keeping the wood inside the housing bare for the bees. There’s inevitably going to be one commenter or two who will choose to make this post about them and dump all over this design for one reason or another. Which is fine (I’ve inhabited a corner of the internet long enough to expect that regardless of the preparedness of a post, someone will get the vapors and require a fainting couch). But I hope for the rest of you, this helps your gardens grow more beautiful and gives you a better way to deal with bees than trying to kill them with insecticide. <3 Enjoy, friends!
See it come to life in the video:
- I had some scrap 1×6, but I highly recommend using even wider boards to make sure that the depth of the 2x4s are enough for various hole lengths while still creating some visible overlap for an overhang (I was working within my limits here but a longer overhang would be even better). Cut two roof pieces using a miter saw set at 22.5° bevel (it’s a preset on many miter saws to cut at this angle because of crown molding, so I went with it).
- Cut two more side pieces with the top also cut to the same bevel so the roof can attach. You can choose to make this housing taller or shorter; the only real difference with that is the height you cut for the sides (make the boards cut a little longer for a taller bee house).
- Cut the bottom piece and back piece with more scrap (for the back, I just used some leftover plywood; it won’t keep forever by being exposed to the elements, but the back of the house and drilled holes will be protected from rain).
- Assemble all pieces together using indoor/outdoor wood glue (such as Titebond II or III).
- Glue together some scrap 2×4 and cut it to a uniform depth once dry. Drill 5/16″ holes or slightly larger depending on the bee species you’re using this for (like I mentioned above, I went with a slightly larger hole based off of the width of the holes I found in my railing).
- Paint the exterior to protect it from the elements. I chose the color Rolling Surf because I think it will go well with what I’ll be planting in my new cutting garden and is a color attractive to bees.
- Hang the new bee house with exterior screws in a place that gets morning sun. Mount the inside 2×4 nesting. I did not secure the inside nesting with screws because I don’t think it will be disturbed here, but you can do so if you think it will come loose.
- Replace the nesting material every year or two years to help prevent rot and parasites.
Measurements and cut list are provided in the free plans and will be available (as of this weekend!) in my Woodworking Plans Library.
Enjoy, and don’t forget to pin this project if you like it!