How to Evict Possums From Your Roof (Legally)

What is the best way to get rid of a possum?

For possums nesting inside a ceiling void, the most effective, long-term approach is humane exclusion using a one-way door, combined with structural proofing. Removing an animal without sealing the primary access point simply leaves a vacant harbourage for the next territorial possum to claim.

Because possums are native, protected wildlife in Victoria, the objective is to secure the building envelope, not to harm the animal or attempt to eradicate wildlife from the local ecosystem.

1. Identify the intruder. Ensure the heavy thumping isn't actually the light, rapid scurrying of a roof rat (Rattus rattus), as rodents require a completely different management strategy.
2. Locate the structural breach. Identify damaged fascia boards, displaced tiles, or gaps under corrugated iron where the animal is forcing entry.
3. Install a one-way eviction door. This allows the animal to exit the roof at dusk to forage, but prevents it from re-entering.
4. Perform permanent structural repairs. Once the roof void is confirmed to be entirely empty (including checking for dependent young), the entry point is permanently sealed using chew-resistant materials.

How to tell whether possums are in your roof

Urban environments support two primary species: the Common Brushtail Possum (Trichosurus vulpecula), which strongly favours roof voids, and the Common Ringtail Possum (Pseudocheirus peregrinus), which typically builds spherical nests (dreys) in dense vegetation but occasionally enters eaves.

Diagnostic signs of a roof infestation

• Acoustic evidence: Heavy thumping, dragging, or loud footsteps occurring primarily at dusk (exiting) and just before dawn (returning).
• Vocalisations: Loud, guttural growls, hisses, or coughing sounds emanating from the ceiling.
• Visual damage: Torn sarking, dislodged roof tiles, or scratch marks on downpipes and timber fascia boards indicating a climbing route.
• Biological evidence: Large, cylindrical droppings (similar in size to a jellybean) on pathways or roof edges, and yellow urine staining seeping through the plasterboard ceiling.

Note: If you hear light, rapid scurrying or scratching inside wall cavities, it is highly likely you are dealing with a rodent infestation, not a marsupial.

The Law: Victorian Wildlife Regulations

Possums are protected under Victoria's Wildlife Act 1975. It is illegal to harass, poison, or harm them. Furthermore, it is illegal to trap a possum and relocate it to a distant park or bushland reserve.

Under Victorian regulations, if a Brushtail possum is trapped inside a building, it must be released on the same property, within 50 metres of the capture site, after sunset. Relocating a highly territorial possum beyond its home range almost guarantees its death due to stress or attacks from resident animals.

This is why professional pest managers focus on exclusion (evicting them from the roof) rather than relocation. For current legislative details, consult the Victorian Government's possum management guidance.

How much does possum exclusion cost?

Based on standard industry pricing, entry-level possum services start at approximately $300–$350. However, a more realistic budget for a standard residential home is $450–$500. Complex jobs requiring extensive roof repairs can exceed $700.

What to do tonight if you hear heavy thumping

1. Do NOT block the hole. Trapping an animal inside your roof will cause it to panic. It may chew through your plasterboard to escape into your living room, or die in the roof void, causing an unbearable odour.
2. Do NOT throw rodent bait into the roof. Poisoning native wildlife carries severe legal penalties.
3. Observe the exterior at dusk. Watch your roofline from the ground just after sunset to see exactly where the animal emerges. This information is highly valuable to your pest controller.
4. Secure your pets. Keep dogs and cats indoors at night to prevent territorial clashes with foraging wildlife.

How to stop them getting back in

Once the roof is certified empty and professionally sealed, you must eliminate the environmental factors that attracted the animal in the first place:

• Remove aerial bridges: Trim tree branches and creeping vines at least 1.5 metres away from the roofline.
• Cap chimneys: Install heavy-duty, galvanized steel mesh over unused chimneys.
• Remove food sources: Ensure outdoor bins are securely latched, collect fallen fruit immediately, and never leave pet food outside overnight.

Dangerous methods to avoid

• Ultrasonic deterrents and flashing lights: These offer no reliable long-term deterrence. Animals quickly habituate to the stimulus.
• Mothballs or chemical repellents: Throwing strong chemicals into your roof void is ineffective, illegal if used off-label, and pushes toxic fumes into your living spaces.
• DIY Trapping: Without a specialized Wildlife Controller license, trapping is illegal and poses severe animal welfare risks.

Frequently asked questions

Can a possum damage my electrical wiring?

While rodents are notorious for chewing wires, possums can also displace wiring, crush insulation, and urinate on electrical fittings. If you suspect wire damage, arrange an assessment by a licensed electrician immediately.

What happens if a baby is left behind in the roof?

This is why professional inspection is mandatory. A licensed controller will physically check the nesting site for dependent young (pinkies or back-young) before installing a one-way door, ensuring families are not separated.

Should I install a nesting box?

Installing a possum box in a nearby mature tree can provide alternative shelter once the animal is evicted from your roof. However, it does not guarantee they will use it, nor does it replace the need to structurally seal your house.