If you hear scratching in the ceiling at night or find droppings in the pantry, the first question is not how to treat the problem. It is what you are dealing with. Houston has both roof rats and Norway rats, and they behave very differently. Roof rats go high. Norway rats go low. Confuse one for the other and your traps end up in the wrong places, your exclusion work misses the entry points, and the problem keeps going.
Quick answer
Roof rats (black rats) are sleek, agile climbers that live in attics, eaves, and upper structures. Norway rats are larger, heavier, and burrow in the ground or along foundation edges. The entry points, nesting sites, and trapping approaches are different for each. Knowing which one you have matters.
Dealing with this right now?
Not sure which rat you have or how they are getting in? Schedule a rodent inspection with Life After Bugs. We will identify the species, trace the entry points, and put a removal and exclusion plan together.
Learn more about our rodent controlin Houston & Katy.
Roof Rats: What They Look Like and Where They Live
Roof rats (Rattus rattus) are the more common of the two in Houston's residential neighborhoods. They are sleek and athletic, with large ears, a pointed snout, and a tail that is longer than their body. Adults typically weigh six to eight ounces. Their coloring ranges from black to dark gray-brown on the back with a lighter belly.
They are excellent climbers. Roof rats enter homes through gaps at the roofline: loose soffits, open ridge vents, gaps around plumbing stacks, and gaps where power lines or cable lines enter the house. Once inside, they nest in attic insulation, inside wall cavities above ceiling height, and in spaces between floors. The scratching or running sounds people hear at night are almost always roof rats in the attic.
Norway Rats: Bigger, Heavier, and Lower
Norway rats (Rattus norvegicus) are noticeably larger. Adults reach twelve to eighteen ounces and look stocky compared to a roof rat. They have smaller ears, a blunter snout, and a tail that is shorter than their body length. Coloring is typically brownish-gray.
Norway rats burrow. You find them in ground-level spaces: under slabs, in crawl spaces, along foundation edges where soil meets concrete, in stacked firewood, or in dense ground cover near the house. They can enter homes through gaps in the foundation, around pipes at ground level, and through floor drains. They are less likely to be in an attic and more likely to be living under a deck or in a space below the first floor.
How to Tell Them Apart Without Seeing One
The location of the evidence tells you a lot. Droppings in the attic, sounds in the ceiling, and chewing on attic insulation or wiring all point to roof rats. Burrows alongside the foundation, droppings at ground level along walls, and damage near floor level suggest Norway rats.
Droppings also differ. Roof rat droppings are spindle-shaped with pointed ends, about half an inch long. Norway rat droppings are blunt-ended and capsule-shaped, a bit larger. Finding both may mean you have both, which does happen.
Different Problems Require Different Solutions
Roof rat control focuses on the upper envelope of the structure. Exclusion means sealing every gap at the roofline: gaps around utility penetrations, loose or missing soffit panels, open ridge vents, and the junction between siding and roofline. Snap traps set along the ceiling joists and entry paths in the attic are more effective than rodenticide bait blocks, which leave dead rodents in the insulation.
Norway rat control focuses on the perimeter at ground level. Burrows along the foundation need treatment. Entry points around floor-level plumbing and foundation gaps need sealing. Traps go in burrow runs and along the interior ground-level walls and floor joists.
Sanitation and exclusion are both part of a complete solution for either species. Open compost bins, accessible pet food, and bird feeders close to the house all create the attractants that keep rats returning after removal.