Roof rats in a Tampa Bay attic: trap, seal, trim, in that order

The first cool nights of October and November bring the same call across both counties: something is running across the ceiling at ten at night. Around the bay that something is a roof rat, Rattus rattus, a slim, dark climber that lives in the live oaks, the palms, the citrus and the attics of Hillsborough and Pinellas. Here is what it is doing up there, how it got in, and why the order of the fix matters more than the product.

How it got in

Roof rats do not use the front door. They come along the oak limb that reaches the roof, the palm frond resting on the gutter, the cable line from the pole, the top of the fence and the trellis, and they enter at the roofline: a soffit return with a gap, a gable vent with a torn screen, the hole cut for the air-conditioner line set and never sealed, the opening at the eave of a barrel-tile roof, the space under a lifted shingle. A rat needs a gap the size of a quarter. On most roofs around the bay there are several.

Once in, the attic is ideal: warm, dry, quiet, full of insulation to nest in and wires to chew. The chewing is the expensive part. Rats gnaw to keep their teeth worn, and the insulation on the AC copper lines, the attic wiring and the plastic drain lines are what they find.

Why poison first is a mistake

The bait box from the hardware store, or the one a company drops in the attic on the first visit, is the fastest route to a worse problem. The rat eats the bait, goes back to the nest in a wall or over the ceiling to die, and the smell lasts two or three weeks in September heat. You cannot find it; the wall gets opened or you wait it out. A rat that eats the bait and makes it outside is taken by an owl, a hawk or the neighbor’s cat, and the poison goes with it. And the bait does nothing about the entry points, so next month’s rat comes in the same way.

Florida does not prohibit rodenticides in a home, and there are jobs where a licensed company uses them in tamper-resistant stations outside. It is the wrong first move, and a company that leads with it is skipping the inspection.

The order that works

Trap. The licensed company inspects the attic and the roofline, finds the runways along the joists and the pipes, and sets snap traps on them, baited with something a bay rat wants: a piece of orange, peanut butter, a raisin. The traps are checked and reset over several visits, a week or two, until nothing new is caught. Glue boards are no substitute; they catch the young and leave the adults.

Seal. When the catches stop, every entry found on the inspection gets closed: hardware cloth and sealant at the soffit returns and the roof-to-wall gaps, new screens on the gable and soffit vents, the AC line penetration foamed and covered, a new rubber sweep on the garage door, the eave closures on a tile roof replaced. This is the exclusion, and it is the part with the warranty. Sealing before the trapping is done locks rats inside, which is how a rat ends up in the living room.

Trim and clean up. Oak limbs cut back from the roof, palm fronds off the gutter, vines off the wall, fallen citrus picked up daily in season, bird feeders moved away from the house, pet food inside, the garage in sealed bins. This is what keeps the next rat from finding the roof, and it is the homeowner’s part.

If the infestation was long, the insulation may be soaked with urine and droppings, and cleaning or replacing it is a separate job with its own quote, sometimes from a separate company.

What the proposal should say

The inspection report, with photos of every entry point and the evidence found. The number of trapping visits included. The exclusion work itemized, and the warranty on it; a year is common, and some companies offer longer with an annual check. Whether attic clean-up is included or separate. The company’s license: rats in a structure are pest control work under the state license, while raccoons, squirrels and opossums in the same attic are wildlife under Florida Fish and Wildlife rules, and the company should say which it is before quoting.

Related pages

• Rat and rodent exterminator
• Pest control in Carrollwood
• Pest control in St. Petersburg