a rodent calendar for a long, hot Dallas year
March through May is the sealing window. Populations are rebuilding outside, the attic is not yet an oven, and a crew can work the roof edge without fighting heat. Anything you close now removes a door before the animals need it. June through August, with highs near 96F, the attic becomes hostile in the middle of the day. rodents do not leave, they redistribute, working soffits, wall cavities, garages and shaded crawl areas where it is cooler. Complaints often quiet down in this stretch, which fools people into thinking the problem resolved itself. September through November is the surge. Outdoor numbers are at their annual peak after a full breeding season, nights cool off, and buildings start looking good again. This is when most attic infestations in Dallas actually establish themselves. December through February is when people finally hear it. Winter lows near 37F are mild enough that outdoor animals are still active, so trapping alone will keep producing catches all season while new arrivals replace them. Sealing is what breaks that loop.
Alleys, dumpsters and the block-level problem
Rat pressure is rarely a single-house issue in an urban grid. Norway rats forage well away from the nest, so a colony living under a neighbor's shed or in a bank along an alley will feed anywhere along that run, and the house with the best opening becomes the one with the noise. On blocks with alley trash service the food supply is steady year round. A dumpster lid that does not close, bagged garbage set out overnight, spilled birdseed, and pet bowls left on a patio all support numbers that no amount of interior trapping will touch. Burrows show up in soft ground near that food, along fence lines, under sheds and next to the slab. The practical response is to fix your own building first, then work outward. Close the grade-level openings and the garage door gap so your house stops being the easy one. Then take on what you control outside: lids, spillage, ground cover and standing water. If neighbors are willing, coordinating even two or three properties makes a noticeable difference, because you are shrinking the food base rather than shuffling animals around.
What a real inspection should hand you
You are paying for findings, so judge the appointment by the document you get. Someone should be in the attic with a light, not just walking the living room, checking the top plates for droppings, the insulation for tunneling, wiring for chew marks, and the eave line for daylight. Outside, the walk covers the entire roof edge, every vent and vent boot, the gap under the garage door, weep holes and utility penetrations, plus any burrow holes along the foundation and fence line. A detached garage or shed gets its own list rather than a note that says the property is clear. The deliverable is a numbered list of openings with a proposed material for each, a call on which species is present and the evidence behind it, a trapping schedule with a number of visits, and a clear answer on whether insulation work is needed. If a company quotes a price before producing that, you are buying a figure rather than a plan, and you have no way to check later whether the work was done.
Heat, ductwork and why attic damage costs more here
In a climate that runs air conditioning for a large share of the year, attic condition is not cosmetic. Insulation that has been tunneled through, flattened and soaked with urine stops performing, and the cooling system compensates by running longer against a 96F afternoon. The second issue is flexible duct. rodents chew and tear the outer jacket and the insulation wrap while moving along the same route night after night, and a torn duct dumps cooled air into an attic that is already the hottest space on the property. People notice it as a room that will not keep up, or a power bill that climbs without explanation, long before they connect it to the noise overhead. Wiring is the risk nobody sees at all. There is no way to inspect it from the living space, which is part of why prolonged attic activity is worth treating as urgent rather than annoying. When you get a quote for exclusion, ask whether the inspector looked at duct condition and wiring while up there, and ask for photos. That single question separates a thorough inspection from a walk-around.
Renters, landlords and getting sealing scheduled
Responsibility divides along a fairly clean line. Closing openings in the shell of the building is a structural repair and normally sits with the owner. Keeping food sealed, taking out trash and not stacking cardboard against a wall sits with whoever lives there. If you rent, document from the first night. Photograph droppings next to a coin for scale, log the dates and times you hear activity, and send the report by email or through the management portal so there is a record with a timestamp. Mention specifically whether the unit shares walls, since rodents move through party walls and utility chases and treating one apartment while the building stays open accomplishes very little. Owners of small rental property in Dallas usually come out ahead by sealing once and doing it properly. Monthly bait service with no exclusion is a recurring charge that never resolves the entry, and by the time contaminated insulation has to come out and go back in, the bill is several times what metal work along the eave would have cost.