It has increased the frequency of the problem.

Homes tend to stand up to harsh rains, as that is normal. What is not normal is 100 almost consecutive days of the heaviest torrential rain I have every witnessed, similar to a tropical wet season.

With this much rainfall, you get your building tested like never before. Our back lawn was flooded most of the time, with the water seeping into the building whatever way it can. There are new roof leaks, persistent puddles that seep into the brickwork. A stream of water running like a river around the property. High humidity means nothing is drying out. And so on...

This year seems the worst we've ever seen in our parts of Eastern Australia - we've also had some of the worst ever floods thanks to La Nina (and climate change), so that's more water than ever. And mould being a living thing keeps spreading when not managed, so it's lingering long after the floodwaters receded.