How to prevent stink bugs from entering the house?

How to prevent stink bugs from entering the house?

In late autumn when temperatures drop, stink bugs seek warm places to overwinter. This is when they are most likely to enter through windows and door gaps in large numbers. Advance preparation can avoid the nuisance of stink bugs indoors.

Seal entry routes

1. Door and window sealing — check if window weather stripping is worn; ensure the gap under doors does not exceed 5 mm.
2. Screen repair — repair or replace torn screens; stink bugs are large but can still squeeze through small holes.
3. Wall gaps — seal exterior wall cracks, air conditioner pipe entries, exhaust fan openings, and wire penetrations with sealant or expanding foam.
4. Balcony closure — for open balconies, install transparent barriers or fine mesh screens on the exterior.

Chemical protective bands

• Spray dinotefuran-containing household insecticide on exterior window sills, sides of window frames, and above and beside door frames.
• South- and west-facing walls are where stink bugs prefer to bask in the sun — spray these areas thoroughly.
• Also spray the exterior foundation of ground-floor homes and yard fences to reduce aggregation density.
• Once dry, the dinotefuran residue forms a film; stink bugs that land on it die. Residual effect lasts 2-4 weeks.

Best timing for control

• Early autumn (September-October) is when stink bugs begin seeking overwintering sites — this is the best time to apply preventive measures.
• In late autumn (November), if stink bugs are already gathering on window sills, reapply insecticide immediately.
• Stink bugs are most active at dusk; spraying at this time is more effective.
• During winter, stink bugs gather in wall crevices, attics, and roofs — from a few to hundreds. They re-emerge in spring, so sealing gaps in autumn is essential.

Daily preventive habits

• Keep windows closed with lights on at dusk; stink bugs are attracted to light.
• If windows are opened for ventilation during the day, close them before dark.
• Bring in outdoor-dried clothes before dark to prevent stink bugs from laying eggs on them.

What if they are already inside?

For a few stink bugs, trap them with a paper cup and release them outdoors; do not swat to avoid odor. If large numbers keep entering, there may be hidden gaps in exterior walls or the roof that need to be found and sealed.