Roof Rats vs Norway Rats in Central Texas
Roof rats climb and live high, in attics and trees. Norway rats dig and live low, in burrows, garages and along drainage. The difference decides where traps go and which gaps get sealed first.
Call a local technician (254) 276-0111Killeen homes can get both of the two common house rats, and they behave differently enough that a plan for one can miss the other. Roof rats (Rattus rattus) are climbers that live high. Norway rats (Rattus norvegicus) are burrowers that live low. Knowing which one you have tells you where to look, where to trap and which gaps to close first.
How they look
Roof rats are slimmer, often dark gray to black, with large ears, a pointed nose and a long tail that is longer than the head and body together. Norway rats are heavier and brown, with a blunt nose, smaller ears and a tail shorter than the body. In the dark, from a quick glimpse, those details are hard to see. Where you find the rat usually tells you more.
Where they live
Texas A&M AgriLife training material describes roof rats as excellent climbers that most often nest above ground and prefer mature vegetation, vines and trees for cover. In a Killeen yard, that means overgrown shrubs, ivy on fences, pecan and oak trees, and from there the attic.
The same material describes Norway rats as excellent swimmers that commonly follow sewers and ditches, with feral populations near woods and streams. They dig burrows. Around a house, look along the foundation, under the AC pad, beside sheds, under wood piles and along fence lines and drainage.
- Roof rats: attic, top of walls, tree limbs over the roof, fence tops, vine-covered fences and sheds
- Norway rats: burrows, garage, crawl space under pier-and-beam houses, ground floor, sheds, along creeks and ditches
What they leave behind
Both leave droppings larger than a mouse's. Roof rat signs show up high: droppings on top of walls in the attic, along rafters and on the HVAC platform, and greasy rub marks on beams. Norway rat signs show up low: droppings along garage walls and baseboards, gnawed holes at the bottom of doors and burrow openings two to four inches across in the soil, with packed paths leading to them.
Sound helps too. Roof rats make running and thumping overhead at night. Norway rats are more likely to be heard in walls near the floor or under a pier-and-beam house.
Why it changes the plan
For roof rats, trapping goes in the attic and along the top of the walls, and sealing focuses on the roofline: soffit gaps, gable vents, plumbing vent boots, where roof planes meet, and the gap at the fascia. Tree limbs should be cut back from the roof. Our rats in the attic article goes through this.
For Norway rats, trapping goes along the garage walls and fence lines, burrows get treated and watched, and sealing focuses on the foundation, garage door, weep holes and crawl space vents. See rodent exclusion for materials.
Many houses get one or the other. Some, especially older homes with big trees and a detached garage or shed, get both. A good inspection will check high and low.
How each one gets in
Roof rats usually come in high. They climb a fence, a tree or a downspout and look for gaps at the roofline: the corner where two roof planes meet, the gap between the fascia board and the roof deck, a gable vent with a torn screen, or a soffit panel they can chew open. Norway rats usually come in low. They dig under slab edges, squeeze under a garage door that does not seal, slip through crawl space vents in older homes, or come up through plumbing gaps from below.
Not sure which you have?
Ask for an inspection. A technician can usually tell within a few minutes from droppings, rub marks and entry holes.
Health risks are similar
Both species can carry germs that make people sick. The CDC says leptospirosis spreads through the urine of infected animals, including rats, and rat-bite fever can spread through bites, scratches and contact with a rodent's saliva or urine. The Texas Department of State Health Services links rats and their fleas to murine typhus. Handle droppings with gloves and never sweep or vacuum them. See rodent diseases in Texas.
Common questions
- Which rat is more common in Killeen attics?
- Attic rats are usually roof rats, since they climb. Norway rats can reach an attic through wall voids but more often stay low.
- Can a Norway rat climb?
- They can climb, but they prefer to stay on the ground and burrow. Roof rats are the stronger climbers.
- Do I need different traps?
- Both need rat-size snap traps. What changes is placement: high for roof rats, low along walls and burrows for Norway rats.
- How do I know if a burrow belongs to a rat?
- Rat burrows are usually two to four inches wide with smooth, packed edges and worn paths leading to them, often along a foundation, fence or under a slab edge.