Late summer brings longer evenings, backyard gatherings, and, if you’re a homeowner in Monmouth County, Ocean County, or parts of Middlesex County, something far less welcome. By August and September, yellow jackets, European hornets, and carpenter ants have had months to quietly establish themselves. And some of them haven’t settled for your eaves or garden beds. They’ve moved inside your walls.
Wall-void infestations are among the most stressful pest situations we encounter at Allison Pest Control. They’re hidden, they’re growing, and they require a very specific response. Here’s what you need to know.
The Interior Buzz: What Does a Wall-Void Infestation Sound Like?
Most homeowners don’t see the nest—they hear it first.
A faint scratching behind the drywall. A low clicking or rustling near an electrical outlet. Sometimes a soft, papery buzzing that seems to come from inside the baseboard. If you’ve pressed your ear to the wall and heard something you couldn’t explain, trust that instinct.
Yellow jackets are the most common culprit behind this phenomenon in late summer across New Jersey. By August, a yellow jacket colony can contain several thousand workers, and as the nest expands, it presses against surrounding materials—insulation, drywall, even wiring. European hornets, which are larger and more aggressive than yellow jackets, also nest in wall voids and are increasingly common in this region. Carpenter ants take a different approach: they don’t build papery nests, but they do excavate galleries through moist or damaged wood framing, creating a distinctive clicking sound as they work.
In every case, the colony you hear is bigger than you think. By late summer, these nests have had the entire season to grow, and they won’t stop until the cold weather forces them to.
How They Got In: Common Entry Points in Home Exteriors
Stinging insects and carpenter ants don’t materialize inside your walls—they find a way in, and usually through an opening that’s surprisingly small.
The most common entry points we identify as exterminators for Monmouth County residents include:
- Gaps in exterior caulking, particularly around window frames, door trim, and where siding panels meet
- Unsealed utility penetrations, such as the openings around electrical conduit, gas lines, cable wires, and plumbing
- Damaged or missing soffit vents, which provide direct access to the space between your exterior walls and interior framing
- Deteriorating mortar or siding seams, especially on older homes where material has cracked or shifted over time
Yellow jackets are particularly skilled at exploiting these entry points. They can squeeze through a gap as narrow as a quarter of an inch, scout the interior void for suitability, and have a new nest underway within days. By the time homeowners notice the problem, the colony is well established.
A late-summer inspection of your home’s exterior is one of the best things you can do for pest prevention in NJ—particularly along the roofline, around utility entries, and at any point where two different building materials meet.
Why You Should Never Seal the Hole Yourself
Here is the most important thing we can tell you, and we say this from over a century of experience in pest control: do not caulk or seal the exterior entry hole if you suspect an active nest inside the wall.
We understand the impulse. You see insects going in and out of a small gap in the siding, you grab a tube of caulk, and you seal it up. Problem solved—or so it seems. In reality, sealing that entry point is one of the most dangerous mistakes a homeowner can make.
Yellow jackets don’t simply give up when their exit is blocked. With thousands of workers and a queen to protect, the colony responds to the blockage by searching aggressively for another way out. That search often leads them inward—through the drywall, through gaps around outlet boxes, and directly into your living space. Homeowners have returned to their kitchens or bedrooms to find hundreds of yellow jackets that chewedthrough the wall from the inside.
European hornets are capable of the same behavior. The results—a sudden, indoor mass emergence of stinging insects—can be genuinely dangerous, particularly for anyone with an allergy to insect venom.
Even if the seal holds temporarily, trapping a colony inside a wall without treating it leaves behind a rotting nest, honey stores that can seep through drywall, and a pheromone trail that attracts new colonies in future seasons.
Do not seal it. Call a wasp exterminator instead.
How Allison Pest Control Handles Wall-Void Infestations Safely
At Allison Pest Control, we’ve been serving Monmouth County, New Jersey and the surrounding region since 1917. Wall-void infestations are something our technicians handle with a specific, methodical approach—one that eliminates the colony without forcing it into your living space and, in most cases, without tearing into your walls.
Our process starts with a thorough inspection to confirm the type of insect, estimate nest size, and identify all entry and exit points. From there, we apply professional-grade treatments directly into the void through the existing entry point, targeting the colony at the source. We time our treatments strategically, accounting for late-summer colony size and behavior to maximize effectiveness.
Once the colony is eliminated, we advise on sealing the entry points properly—after the nest is inactive, not before. For carpenter ant infestations, we also assess any underlying moisture issues that made the wall void attractive in the first place.
Don’t Wait for the Problem to Come Through the Wall
Wall-void infestations don’t resolve on their own. As late summer peaks, colonies are at their largest and most defensive, and the risk of an interior emergence grows with every week you wait.
If you’re hearing unexplained sounds inside your walls, or noticing consistent insect activity around a specific point on your home’s exterior, schedule a free pest inspection with Allison Pest Control. Our team will assess what’s happening and recommend the safest, most effective solution—before the problem gets worse.
Ask us about our year-round Home Protection Plans, which provide ongoing coverage for the pest pressures that affect Monmouth, Ocean, and Middlesex County homes across every season. Call us or complete our online form to get started.
