The Simple Way To Prevent Carpenter Bees From Drilling Into Your Deck Or Siding

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There is a simple way to prevent carpenter bees from drilling into your deck or siding that doesn't involve extermination. These loud insects live up to their name: They love to burrow into wood and create intricate networks of tunnels, leading to a carpenter bee nest in your yard. This can be quite annoying. If you've mastered the DIY homeowner's guide to deck building, you likely don't want all your hard work ruined — even if it is by such a good pollinator that's nice to have around! The simple way to keep carpenter bees out is to prevent them from having easy access to the wood. You can do this by sealing any imperfections, such as cracks and holes, in its surface with wood filler, wooden pegs, or caulk. If the bees can't get to the vulnerable parts of the wood to start drilling, they might build somewhere more appropriate, like a nearby stump. 

Any nicks in the planks' surfaces or damage (like dents from a recent hail storm, for example) can offer the bees a nice starting place, leading them to drill down further to build their nests. For small bits like screw holes, you can use a wood filler, like Minwax Color-Changing Natural Wood Filler. It prevents the insects from drilling because it's a thick putty. It clogs the hole with non-wood material, making the bees uninterested and pretty much unable to dig in. Make sure to pick a filler that's been formulated for outside, as you don't want exposure to the elements to undo the preventative steps you've taken. 

At their core, these insects love to bore into unpainted, non-stained softwood — add holes and cracks to this and they are in heaven. Any sort of barrier between the bees and the wood is an effective preventative measure. Just remember that before you take any steps to seal off holes, make sure that there isn't a carpenter bee already inside.

In addition to wood filler, you can use caulk to prevent bees from boring into your deck or siding. There might be longer, straight gaps to fill in and latex caulk in particular seals them up easily. Go slow, so you don't have to learn how to fix messy caulking later on. If the hole in your deck or siding is too large for wood filler or caulk to effectively cover over, you can keep out carpenter bees by using a small wooden peg to fill the space instead. You can buy these ready-made. They are sometimes called dowels. After measuring the size of the hole to ensure the dowel gets a tight fit, secure the exterior of the peg with exterior wood glue so that it stays in place.