Roof rats are attracted to food, water, and shelter — and your attic provides all three
Roof rats nest in your attic, walls, and roof voids because those spaces are warm, dry, and hidden from predators. They enter through gaps in soffits, vents, fascia boards, and roof penetrations as small as a dime. Once inside, they chew wiring, insulation, and wood framing, and their droppings contaminate insulation and create odor problems. Getting rid of them requires three steps: removing their food sources, sealing entry points, and trapping or poisoning the rats already inside.
The most common mistake homeowners make is trying to poison rats without first sealing the house. Poison kills some rats, but new ones will keep entering through the same holes. You have to do both — trap and seal — or the problem returns within weeks.
Key Takeaways
- Roof rats enter through openings smaller than a dime in soffits, vents, fascia, and around pipes; sealing these gaps is the only permanent solution.
- Remove food sources by securing garbage cans with locking lids, cleaning up fallen fruit and nuts, and storing pet food indoors in sealed containers.
- Snap traps and electronic traps kill rats faster and more reliably than poison, which can leave dead rats hidden in walls where they decompose and smell.
- Trapping works best when you place traps along walls where rats travel, bait them with peanut butter or nesting material, and check them daily.
- After you have trapped the rats, hire a pest control company or roofer to seal all entry points with hardware cloth, steel mesh, or caulk to prevent reinfestation.
Remove food and water sources first
Roof rats will leave if there is nothing to eat. Walk your property and remove or find anything they can feed on: fallen fruit and nuts under trees, pet food left outside, birdseed, compost piles, and garbage. Bring pet food indoors at night and store it in sealed metal or plastic containers. Use garbage cans with locking lids or store them in a sealed shed until pickup day.
Check your roof and gutters for debris that collects water. Roof rats need water daily, and a clogged gutter or a slow leak can sustain a population. Fix leaks, clean gutters, and remove standing water from tarps or low spots on the roof. If you have a bird bath or outdoor water source, move it away from the house or drain it at dusk.
Seal entry points with hardware cloth and caulk
Roof rats enter through small, overlooked gaps. Walk around your house and look for openings in the soffit (the underside of the roof overhang), fascia boards, vents, and around pipes and wires where they enter the attic. Check where the roof meets the walls, around dryer vents, and under eaves. Any opening larger than a quarter-inch should be sealed.
Use hardware cloth (a metal mesh) or steel mesh for larger gaps and around vents — rats cannot chew through metal. Caulk smaller cracks with silicone caulk or expanding foam. Do not use plastic or rubber; rats chew through both. If you are not comfortable on a ladder or roof, hire a roofer or pest control company to do this work. Sealing is the only permanent fix, and it is worth the cost.
Pay special attention to roof vents, which are common entry points. Install vent covers made of hardware cloth or buy pre-made vent guards designed to keep rats out while allowing airflow. Dryer vents should have a one-way flapper that closes when the dryer is off.
Trap rats inside the attic and walls
Snap traps and electronic traps kill rats faster than poison and are safer for pets and children. Poison can take days to work, and poisoned rats often die inside walls or attic cavities where they decompose and create a strong smell that lasts weeks. Traps kill when ready and you can remove the body right away.
Place traps along the walls where rats travel — they run along edges, not across open spaces. Bait them with peanut butter, chocolate, or nesting material like cotton balls or dryer lint. Rats are curious and will investigate. Check traps every morning and evening. Wear gloves and a mask when handling dead rats, and dispose of them in a sealed bag in the trash.
If you find rat droppings in the attic, place traps near those areas. If you hear scratching in the walls at night, set traps in the attic near the wall cavity. You may need to set 5 to 10 traps to catch all the rats in the house. It usually takes one to two weeks of daily trapping to clear an infestation.
When to call a pest control company
If you have a large infestation, rats in multiple areas of the house, or you are uncomfortable trapping them yourself, hire a pest control company. They have commercial-grade traps, know where to place them, and can seal entry points. Many offer a warranty — if rats return within a set period, they will re-treat for free.
Get quotes from at least two companies. Ask what they will do to seal the house and what warranty they offer. Some companies use poison only, which is cheaper upfront but often fails without sealing. Choose one that will both trap and seal.
Why poison alone does not work
Poison kills some rats, but new ones will enter through the same holes. Poison also takes days to work, and rats often die in inaccessible places — inside walls, under insulation, or in roof cavities. A dead rat in a wall smells for weeks and attracts flies. You cannot remove it without opening the wall.
Poison is also risky if you have pets or children. A pet can eat a poisoned rat or the poison itself. Trapping is faster, safer, and more effective. Use poison only if you have already sealed the house and are certain all rats are dead — then poison is a backup measure, not the main solution.
Prevent roof rats from returning
After you have trapped all the rats and sealed the entry points, keep them out by maintaining the barriers you built. Inspect the roof and soffits twice a year for new gaps or damage. Trim tree branches that hang over the roof — rats use them as highways into the attic. Keep branches at least 6 feet away from the roof edge.
Continue removing food sources: find garbage, clean up fallen fruit, store pet food indoors, and fix any water leaks. A single unsealed gap or a reliable food source can start a new infestation. The effort to prevent reinfestation is much smaller than the effort to clear an active infestation.
Frequently Asked Questions
How do I know if I have roof rats and not mice?
Roof rats are larger — about 6 to 8 inches long, not counting the tail. Their droppings are bigger and shaped like a grain of rice. Mice leave smaller, thinner droppings. Roof rats also make louder scratching and running sounds in the attic, especially at night. If you see a rat, it will have a long, scaly tail and large ears.
Can I use poison if I have pets?
Poison is risky around pets. A dog or cat can eat a poisoned rat or the poison itself. If you must use poison, place it in a locked bait station that only rats can enter. Snap traps are safer — they kill when ready and you control where they are placed. Keep traps away from areas where pets sleep or eat.
How long does it take to get rid of roof rats?
Trapping usually takes one to two weeks if you set multiple traps and check them daily. Sealing the house can take a few days to a week depending on how many entry points you have. If you hire a pest control company, they may finish in one visit, but you should wait a few weeks after sealing to confirm no new rats enter before you consider the problem solved.
What if I hear rats in the walls after I have sealed the house?
You may have sealed rats inside the walls. Set traps in the attic and near the wall cavities where you hear noise. The rats will die within a few weeks from starvation if they cannot find food. Once the noise stops, the rats are dead. If noise continues for more than a month, you may have missed an entry point — hire a pest control company to inspect for gaps you cannot see.
Do I need to remove insulation after a rat infestation?
If rats have contaminated the insulation with droppings, it should be removed and replaced. Rat droppings can carry hantavirus, which is rare but serious. If the contamination is light and localized, you can clean it with a damp cloth and leave the insulation. If it is heavy or spread across a large area, hire a professional to remove and replace it. This is especially important in the attic where you may spend time.