The Truth About Stink Bugs & Lady Beetles Hiding in Your Walls

Why They Invade in November — and What You Should (and Shouldn’t) Do About It

As the weather cools and homes across Alabama get a little cozier, two familiar fall invaders start showing up: brown marmorated stink bugs and Asian lady beetles. You might see them on your windows, clustering around the sunny side of your house, or randomly appearing inside your home. And here’s the real reason they seem to come out of nowhere:

✅ They’re already inside your walls.

If that sounds unsettling, don’t worry — you’re not alone. These overwintering pests sneak in during late fall, get comfortable in hidden voids, and then show themselves when temperatures fluctuate.

This blog breaks down why they do this, what it means for your home, and the right way to deal with them.

Why Stink Bugs & Lady Beetles Invade in November

Both pests follow the same winter survival strategy: find a warm, protected place to hide until spring. Your home checks every box.

1. They’re attracted to warmth and light

The sunny side of your home heats up during the day, and these bugs gather there looking for cracks and gaps.

2. They slip into tiny entry points

Common entry routes include:

• Gaps in siding

• Cracks around window frames

• Unsealed door sweeps

• Attic vent screens

• Utility line openings

Once inside, they crawl deep into wall voids, attics, and insulation.

3. They “shut down” for winter

This is called overwintering — the insect version of hibernation. They stay hidden until warmth wakes them up.

Why You Suddenly See Them Inside Your Home

Most homeowners think stink bugs or lady beetles are coming in when they find them indoors. In reality:

✅ They’re coming OUT.

Warm spells in winter or a heater running inside the home can cause them to stir and accidentally wander into living spaces.

You’ll often find them:

• On windowsills

• Around light fixtures

• Near ceiling corners

• Crawling on walls

• Appearing one at a time over several months

This slow trickle is typical for overwintering pests — and it doesn’t mean they’re actively breeding inside.

The Good News: They’re a Nuisance, Not a Threat

Neither stink bugs nor lady beetles bite, sting, or damage your home’s structure.

However… they are annoying:

• Stink bugs release a strong odor when threatened.

• Lady beetles leave yellowish stains when crushed and can release a foul-smelling chemical.

• Both can show up for months due to fluctuating temperatures.

But the real problem is preventing next year’s invasion — because overwintering pests return to the same homes year after year.

What NOT to Do When You Find Them Indoors

Homeowners often make harmless pests much worse with the wrong approach. Here’s what to avoid:

❌ Don’t crush them

Most will release odor or stains.

❌ Don’t spray indoor pesticides

Over-the-counter sprays won’t reach the ones hiding in walls and can create unnecessary chemical exposure inside your home.

❌ Don’t block attic or crawl vents

Airflow is important for your home’s structure — and pests can still find other ways in.

What You Should Do Instead

Here’s the safe and effective approach:

✅ 1. Vacuum them up

Use a shop vac or a vacuum with a disposable bag. (Throw the bag out when done to avoid lingering odor.)

✅ 2. Seal up gaps and cracks

Late fall is an excellent time to tighten up your home:

• Caulk around windows

• Add door sweeps

• Replace torn screens

• Seal utility penetrations

• Check soffits and roofline gaps

✅ 3. Treat exterior surfaces — at the right time

The best time to prevent stink bugs and lady beetles is before they enter the home, ideally in the fall. A professional perimeter treatment stops them from slipping inside.

✅ 4. Maintain a winter pest control plan

Even though overwintering pests hide quietly, they rely on seasonal cycles. Continuing service through winter keeps numbers low and prevents repeat invasions.

How Dave’s Pest Control Can Help

Stink bugs and lady beetles are frustrating because you often don’t know they’re inside your walls until it’s too late. At Dave’s Pest Control, we use:

• Targeted exterior treatments

• Entry-point inspections

• Attic and crawlspace assessments

• Preventive seal-up recommendations

This approach helps stop overwintering pests before they settle in for the season — and keeps your home protected all winter long.

Say Goodbye to Surprise Winter Visitors

If these little invaders are popping up around your home this November, don’t worry — you’re not dealing with an infestation, just seasonal behavior. With the right prevention plan and a little help from Dave’s Pest Control, you can stop them from returning year after year.