Quick Answer
Walk your house at eye level and roofline and you'll usually find the hole before the animal does. The nine spots wildlife use most in fall: roof and gable vents, soffit seams, the chimney, utility penetrations, ridge vents, dryer vents, brick weep holes, garage and foundation gaps, and roofline gaps where branches touch. Seal them before the first cold snap — but never before confirming the attic is empty.
The Fall Move-In Pattern
I've been sealing houses against attic animals around Austin for fifteen years, and fall is the season that keeps me busy. When the nights cool off in late September, squirrels, rats, and raccoons stop treating your house as scenery and start treating it as a den. Most of the houses I walk end up having not one gap but three or four — the animals just use the easiest one.
If you've already heard noise, start with squirrel in the attic: sounds, signs, and prevention to figure out what you're dealing with. This guide is about the holes themselves.
The Nine Entry Points
Here's the walk I do, in the order I do it. For each spot: what I look for, and what actually fixes it.
1. Roof & Gable Vents
Look for: torn screens, chew marks on the frame, or a vent that's been pushed in.
Fix: Remove the screen and staple 1/4-inch hardware cloth over the opening before reinstalling. Hardware cloth is the only mesh that reliably stops squirrels and rats.
2. Soffit & Fascia Seams
Look for: lifted or pulled-apart sections of soffit, especially at corners and where sections meet.
Fix: Screw the section back, then cover the seam with metal flashing or hardware cloth so they can't pry it open again.
3. Chimney
Look for: a missing cap, or the sound of anything fluttering or rustling inside.
Fix: Install a proper chimney cap with mesh. Never seal a chimney without confirming nothing is inside — animals that fall in can't get out.
4. Utility Penetrations
Look for: gaps around plumbing pipes, electrical conduits, and cables where they enter the house.
Fix: Pack the gap with steel wool and seal over it with caulk. Rats and mice squeeze through surprisingly small openings.
5. Ridge Vents
Look for: lifted sections or gaps along the ridge line.
Fix: Re-seat the vent and lay hardware cloth underneath it. This one usually needs roof work — call a pro if you're not comfortable on a roof.
6. Dryer Vents
Look for: a missing flap, a loose grille, or a vent that doesn't close all the way.
Fix: Install a vent guard with a flap that seals when the dryer isn't running.
7. Brick Weep Holes
Look for: open weep holes at the base of brick veneer.
Fix: Insert wire mesh plugs made for weep holes — they let moisture out but keep mice out.
8. Garage & Foundation Gaps
Look for: daylight under the garage door, worn weatherstripping, or gaps where the foundation meets the siding.
Fix: Replace weatherstripping, and fill foundation gaps with steel wool plus caulk or mortar.
9. Roofline & Branch Contact
Look for: branches or vines touching the roof, or a gap where the roof meets the fascia.
Fix: Trim branches back at least six to eight feet. Cover any roofline gap with metal flashing.
The Rule That Comes First: Never Seal an Animal Inside
Every one of these fixes comes with the same warning: confirm the space is empty before you close it. Sealing a mother with babies inside is worse than leaving the hole. I always tell homeowners to listen at dawn and dusk, look for a nest, and use a one-way door if anything is still coming and going. If you're finding chewed wires, that's a fire risk worth handling fast — see what animal is chewing wires in the attic.
Materials That Actually Work
| Material | Best For | What to Avoid |
|---|---|---|
| 1/4-inch hardware cloth | Vents, soffits, ridge lines | — |
| Steel wool | Small gaps around pipes and wires | — |
| Metal flashing | Roofline and soffit seams | — |
| Expanding foam | Filler only | Don't rely on it alone — squirrels chew through it |
| Wood filler / caulk alone | — | Too soft for chew-prone spots |
A Fall Timeline That Works
- Early September: trim branches, do the walk-through, fix the easy low gaps
- Mid-September: seal vents, soffits, and utility penetrations
- Late September: finish roof-line work — call a pro for heights
- October on: listen once a week; if you hear something, fix the gap before it becomes a den
State-Specific Notes
Rules and protected species differ by state, and so do the best prevention habits. If you're in a state with a colder climate, the timeline shifts earlier. These guides cover the specifics: New York squirrel attic guide, Washington wildlife attic guide, and Virginia wildlife attic guide.
FAQ: Animal-Proofing Your Home
What time of year do animals get into attics the most?
Fall, when temperatures drop and animals start hunting for a warm, dry den for winter. Spring is second, when mothers look for safe nesting sites.
Can I use expanding foam to seal squirrel holes?
Not alone. Squirrels and rats chew through foam quickly. Use it as a filler and back it with steel wool or hardware cloth.
Will sealing the attic trap animals inside?
It can, if you seal before confirming the space is empty. Always check for a nest and active animals first, and use a one-way door if needed.
Do I need a permit to animal-proof my own home?
For your own house, usually no — but animals like bats may be protected, and eviction of protected species can require a licensed professional. Check your state wildlife agency before you start.
What if I find a raccoon with babies?
Don't seal them in and don't try to remove the mother yourself. Call a wildlife removal professional — reuniting and excluding properly is a job for experience.
Sources: NPMA, CDC, Texas A&M AgriLife Extension, US Fish and Wildlife Service, state wildlife agencies. This guide is for informational purposes only and does not constitute professional wildlife management advice.