I now store seasonal clothing in sealed bins and plastic bags. It’s extra work, but I’ve frustrated re-infestations about 90% of the time.
For serious infestations, professional services offering residual sprays often cover cracks, moldings, and hidden voids. Worth checking their experience with carpet beetles.
In one job, I found the infestation source was behind baseboards and inside attic insulation. You can’t just treat floors, look upward, inside walls.
@PestPhobia I agree, if you only kill adults and miss larvae, they’ll come right back. You have to treat all life stages to truly reduce numbers.
Pheromone sticky traps help monitor how many adult beetles are active. That gives you a gauge whether your control steps are working.
Honestly, carpet beetles sometimes never go away 100%. The goal is to push numbers so low you hardly ever see them, and maintain with cleaning, exclusion, and monitoring.