Can Carpenter Bees Eat Through Caulk? Find Out

by Derrick | Last Updated: May 2, 2022

Carpenter bees are seen as a nuisance because they cause structural and aesthetic damage to a home, especially since they tend to tunnel through the same piece of wood year after year. Many homes these days are reinforced with waterproof sealants or caulk, but it takes a lot to keep carpenter bees from boring down into your home!

Carpenter bees can eat through caulk. The rubbery consistency may make it more difficult for them to chew, but they will eventually succeed given enough time. To reinforce caulk, consider adding another barrier, such as stainless steel wool. 

So, let’s talk about how you can prevent carpenter bees from getting cozy in your home and ways to drive them away if they’ve already settled in. I will focus on what you can do to make caulking an effective way to keep these bees away. Then, I’ll touch on why carpenter bees do this in the first place and what may be attracting them to your home.

How To Stop Carpenter Bees From Eating Through Caulk

Carpenter bees, particularly females, have strong mandibles. They use these to chew through wood to make tunnels and build their nests. Unfortunately, these strong mandibles could also chew through caulk, so your efforts in sealing those tiny holes you just found may go to waste. 

One way to make it more challenging – and hopefully impossible – for carpenter bees to escape from or re-enter these sealed tunnels is by reinforcing the caulk with steel wool. 

So, here’s how to stop carpenter bees from eating through caulk: 

  1. Spray a piece of steel wool with insecticide. 
  2. Plug the hole with large chunks of the insecticide-soaked steel wool.
  3. Caulk over the steel wool to effectively seal the hole. 

The carpenter bees will first chew through the insecticide-laced steel wool in an attempt to escape. Due to the toughness of the steel wool, it will take much longer for the carpenter bees to chew through it, giving the bees time to die before they can make it out (or in). 

Why Do Carpenter Bees Tunnel Through Wood?

Carpenter bees tunnel through wood to lay their eggs and rear their young. Female bees do all the hard work. They create an opening in the wood with their strong mandibles, then tunnel through to build an intricate series of small cells. These tunnels could go as deep as 1-4 feet (0.3-1.2 m).

Male carpenter bees guard the nest, while the females make themselves at home in any piece of bare wood they can find. They might appear daunting with all their hovering and buzzing about, but, unlike the females, they do not have stingers. 

It is crucial to eliminate these tunnels as soon as you find them in your home. Adult carpenter bees tend to go back to the same wood where they hatched, year after year during spring. They will rebuild and modify these tunnels, making the wood weaker and more susceptible to decay over time. 

How To Tell if Carpenter Bees Have Invaded Your Home

It is easy to tell if carpenter bees have invaded your home. Here are a few signs to watch out for: 

  • Drilling sounds: You might hear soft drilling or grinding sounds in the wood as the female carpenter bees tunnel through it to build their nest. 
  • Bees hovering around wooden structures : You might notice bees frequently buzzing around a particular spot. These are probably male carpenter bees guarding the nest as the females work inside. 
  • Tiny holes: The most telling sign is if you find tiny holes in the wood, often with nectar, pollen, or sawdust around them. These early boreholes mean that carpenter bees have already claimed this spot as their home. 

You might mistake carpenter bees for bumblebees. Note that carpenter bees do not have yellow hairs on their abdomen as bumblebees do. Also, you will rarely see carpenter bees buzzing among flowers and plants the way bumblebees do. Carpenter bees would be hovering near your roof, porch, eaves, garage, wooden furniture, or around a wooden structure. 

What Attracts Carpenter Bees

Apart from wood, there might be other things within your property attracting carpenter bees year after year. Here are some of them: 

  • Flowers: Carpenter bees thrive on nectar and pollen from flowers like all other bees. Your garden may be bursting with blooms in the springtime, but these flowers are certainly doubling as welcome signs for these bees and other insects. 
  • Old carpenter bees nests: Carpenter bees are pretty smart. They would pick an old bee nest over a fresh piece of wood anytime. Instead of building their nests from scratch, they will take over the old nest and expand it to their liking. So, it is vital to properly seal these nests if you don’t want to keep attracting carpenter bees to your home every spring. 

How To Get Rid of Carpenter Bees

Nobody would like to share their home with a family of carpenter bees. However, it can be challenging to keep them out. 

So, to keep up with them, you’ll need to drive them away, or better yet, keep them from even trying to approach your home. 

Note: Keep in mind that female carpenter bees may sting when they feel threatened. It would be best to wear protective gear when dealing with them. Consider making your move at night because carpenter bees are less active when it gets dark.

Here are some suggestions for eradicating your carpenter bees: 

  • Coat the wood with stain or paint: Do this before spring arrives or before carpenter bees start choosing locations for their nests. A layer of wood stain or paint will do wonders in stopping these bees from making a home on your property. If you can, go for oil-based or polyurethane-based exterior finishes because these provide extra protection against carpenter bees. 
  • Spray: Consider spraying your home, especially wood exteriors, with insecticidal spray. The spray will keep bees away and may kill some other insects or pests that have already settled into your home. Go for an insecticide with pyrethrin as one of its active ingredients since it is proven effective in keeping carpenter bees at bay. 
  • Borax: Borax used to be a go-to option for killing carpenter bees. However, borax works slowly and gives the bees more time to damage your home. It is also toxic to birds and pets. More importantly, it causes skin irritations and can hurt your eyes upon contact. The powdery substance can also cause complications to the throat and lungs when inhaled. So, be cautious and only use borax as a last resort!
  • Seal the entrance: Sealing old carpenter bee nests is a must. Closing up shop will discourage them from returning to your home – which has become their home too – the following spring. Plug the entrance hole with putty, carpenter’s glue, or caulking. Remember that these sealants will not be effective when used on their own since carpenter bees can eat through them. Reinforce with steel wool. 
  • Citrus oil: Citrus oil acts as a natural repellent for carpenter bees because they hate the smell. You can spray citrus oil into newly drilled holes to stop the bees from making their nests or over wood surfaces as a natural deterrent. 
  • Wind chimes: Carpenter bees do not like feeling vibrations around their nest. You can drive them away by installing chimes near where they’re drilling. 
  • Give them their own home: Like all other bees, carpenter bees play an essential role as nature’s pollinators. They are one of the main reasons we have flowers blooming in our gardens every spring. Hang a carpenter bee home in a spot where they won’t be bothersome for anyone. These have pre-drilled holes that are very inviting for female carpenter bees eager to provide a safe home for their young. 

Final Thoughts

Dealing with unwanted springtime carpenter bee visitors every year can be such a chore. Find a strategy that works for you. 

Caulking is one of the more effective ways to keep these bees at bay, but remember that they can chew right through the rubbery consistency. Fortify it with good old steel wool and some insecticide, and you may never have to share your home with carpenter bees again.