They may be welcome occasional visitors but possums are never welcome house-guests!

If you have ever had a possum in your roof you know the disruption these otherwise cute animals cause to your nights, not to mention the damage they do to your house.

At night they race around in your ceilings and scamper noisily across neighbourhood roofs looking for food and avoiding the dogs and other dangers on the ground.

In their search for accommodation they dislodge roof tiles and cappings, and eat through timbers.

In your ceiling they move insulation around to make nests, can damage roofing timbers and electrical wiring, tear ductwork, leave droppings, and stain your plaster ceilings with their urine.

Possum fact file

There are two common types of possum in suburban Australia, the large and cheeky brushtailed possum and the smaller and more timid ringtail possum. Both are protected under the Wildlife Act 1975 – you can’t harm them and you can’t keep them (unless you have a permit from the government department that protects wildlife in your State).

Possums are strong for their size, which is why the larger brushtail can do so much damage to roofs. They can easily lift loose roofing materials (galvanised iron or tiles) while looking for a new ‘tree hollow’ to call home.

Possums can carry lice and other undesirable insects, making them a health hazard, and they can die in your roof, leaving a very unpleasant smell as well as attracting flies and vermin.

Possums have a home range, usually an area of about 50-metre diameter.

Evicting a possum

If you already have a possum tenant, you need to relocate it before you can possum-proof your house.

The law allows you to ‘interfere’ with a possum if it is in your roof, so you can trap it as it leaves your ceiling space for its nightly ramble. Some local councils have traps for hire, or you can hire a professional to do the trapping for you. Remember that you are dealing with a strong wild animal with sharp teeth and claws that can behave unpredictably when stressed.

You can only release a trapped possum at night, in its own territory (that is, within 50 metres of where you caught it).

To discourage the possum from trying to return, put a cool light (fluoro tube) in the roof cavity for a few nights and spray around the entry point with disinfectant or a commercial or home-made repellent to remove or mask the possum’s scent.

  • Providing alternative accommodation is likely to make the eviction more successful. Before you trap and release your possum, put up a nesting box in a nearby tree (avoid facing west). Add some fruit pieces as a further enticement.
  • Don’t use bleach or other harmful chemicals to remove the possum scent because these can be poisonous to possums.
Exclusion is better than eviction

With natural nesting sites becoming rarer in built-up areas, your roof can check all the boxes for a house-hunting possum: it’s warm, it’s weatherproof, it’s safe, it’s a perfect dark place to sleep through the day, and they can’t be evicted easily.

Keeping possums out is easier than trying to dislodge one that has taken up residence.

First, check for access points. Ringtails can get through a hole as small as a credit card and brushtails can jump up to five metres.

If you are confident there are no possums in your roof, seal all the holes firmly, including repairing loose tiles and deteriorating capping and fixing loose iron.

Possum-proofing after an eviction

If you are possum-proofing after an eviction, be even more scrupulous about finding all access holes. If you can, go into the roof space during the day, sunlight will show you where the gaps are.

Trees and shrubbery

Trees and tall shrubbery are the most common ways possums get from the ground to your roof. If you have a tree within jumping distance of the house, wrap wide rigid aluminium or plastic guards around the trunk at least two metres off the ground. This prevents the possum running up the tree. Remove branches less than five metres from the ground. Trim tall shrubs and move anything else the possum can use to get onto the trunk above the guard.

Gutter protection

Gutter protection is an easy way to stop possums nesting in your gutters, using your gutters to get under the eaves and into the roof cavity, or getting washed into the downpipe in a storm (with fatal consequences for the possum and unpleasant consequences for you).

Other possum deterrents

Bright lights: Like all nocturnal animals, possums dislike bright lights (which is the reason for facing a nesting box away from the west, where the sun is setting when the possum is getting up). A motion-activated spotlight can discomfort them and stop them settling.

Ultrasonic repellers: These emit sounds that humans can’t hear but are unsettling to possums.

Finally, remove as many temptations as possible. Make sure possums can’t get into your rubbish bins, keep pet food indoors if possible, and put bird feeders out of possum reach.