Rats in the Walls: How to Tell and What to Do in Florida
The short answer: scratching or scurrying inside a wall at night, with droppings or gnawing nearby, usually means rats. In Florida it's often roof rats moving between the attic and food below. Seal the gaps they use, then trap the rats inside along their paths. Poison can leave a dead rat in the wall. Call (844) 264-6254.
How to tell it's rats
- Night noise. UF/IFAS says rats are most active at night, and Florida DOH says roof rats peak about an hour after sunset and an hour before dawn (Florida DOH).
- Droppings or urine stains, which UF/IFAS calls the usual first signs. Check baseboards, cabinets and under sinks (UF/IFAS).
- Rub marks and gnawing. UF/IFAS Extension in Duval lists droppings, urine, rub marks and gnawing as the tell-tale signs, and DOH describes dark grease stains where rats run.
- Sounds that move up and down, which suggests rats traveling between the attic and floor level.
If you're not sure it's rats, our guide to what animal is in your attic compares the usual suspects.
Roof rats or Norway rats?
Florida DOH says roof rats prefer high places such as attics, while Norway rats tend to stay on lower floors. Roof rats are strong climbers: UF/IFAS says they can jump three feet straight up and more than four feet across, and recommends pruning limbs away from the house (UF/IFAS). More on telling them apart in Norway rat vs roof rat.
How they get into the walls
UF/IFAS says rats can get through gaps of about half an inch, and DOH notes roof rats need only a hole the size of a quarter. Common routes are roof returns, gaps where pipes and A/C lines go through the wall, and openings under the eaves. UF/IFAS Extension in Duval warns that rodents easily chew through spray foam (UF/IFAS). UF/IFAS Extension in Santa Rosa says to close gaps with mortar, concrete, sheet metal or 19-gauge hardware cloth with no openings over ¼ inch (UF/IFAS).
Trap, don't poison, inside walls
- Snap traps are a low-cost option, UF/IFAS Extension in Pinellas says, and glue boards aren't humane because they prolong death (UF/IFAS).
- Place traps along walls, near holes, or across beams and rafters where rats travel, as UF/IFAS advises.
- Poison is a last resort. Pinellas Extension says rodenticides can take several days to kill, and UF/IFAS says toxic baits are legal only for non-native rats and house mice and must be in bait boxes (UF/IFAS).
Why bait can end with a smell
Poisoned rats don't die on the spot. Our dead animal smell guide has UF/IFAS's timeline for anticoagulant bait (UF/IFAS), and by then a rat may be back inside the wall it lives in. That guide also covers what to do if it happens.
The usual order
- Inspect the roofline, attic and outside walls for every gap.
- Seal the openings, leaving none the rats can still use.
- Trap the rats left inside along their paths, and check the traps often.
- Clean up droppings with gloves and disinfectant, never by sweeping or vacuuming.
See rat removal, rats in the attic and rat removal in Tampa, or call (844) 264-6254.