Yes, it can done. However, I been told many times by the contractors working on the roof or gutter or random people, that it is not possible to possum proof my house because it is surrounded by forests, the tree branches are hanging just above the roof and it has too many angles – entry points for the possum. When we close one entry hole, they will dig another one straight away using their strong crows.
We had possums come in and out of the roof nearly every day for the past 20 years, some times they are knocking behind the plaster walls during day time, we did not have real problem with that before. Well, just to say that we were able to put up with the small inconvenience – can’t tell if its possum or ninja visiting the arctic, and occasionally sweeping dropping of the possum or facing the big rat looking figure on the windscreen.One of the Autumn night, my family suspected something smell off, next day we were able to confirm the suspicion with strong odour and google madly for the help. We found this wonderful company that were able to come first thing next day and remove the dead body, confirmed it was a dead possum. For the price of $250, he deodorised the roof and take away the dead body, I don’t want to get into too much of gruesome detail -just say that if you want to inspect the job you can. Be prepared that the smell linger around for another 3 days even after deodorised, it was a very foul smell – well, its the dead possum smell. In this experience I also found that I can roof proof for possum and delighted to know that the price is under $250 with 1-3 years warranty!
Knowing this of course I asked the nice guy to come back and do the job, which involve seal off the roof, set a cage and come back next few days to remove the cage in case the possum were inside the roof when roof are sealed. You know that possums are protect animals and you can’t kill them or take them too far away from their home otherwise can kills them?
I have been sleep sound without have to worry my ninja visitors for 2nd months now. Very happy with the result, so far so good, I will update you if condition changed.