[esperent]

I've unfortunately lived in too many houses where mold becomes a problem. It's never my fault, it's always been because the house is old/doesn't have proper damp proofing/cheap paint was used, or no damp proofing applied on exterior walls. I clean it, of course, so I'm not literally living in a house with moldy walls, and I keep the house as dry and ventilated as possible. But in certain climates it's nearly inevitable to get mold during winter or the humid season unless the house is very well built and modern.

The worst, and again very common, is when the paint is so cheap it can't be cleaned easily - when you use anything that can actually clean the mold (soapy water + a bit of vinegar is my preference, but baking soda, very weak bleach solution, or commercial mold cleaners) it also destroys the paint.

[HPsquared]

There is specific kitchen / bathroom paint that is smoother and has some anti-mold ingredients. Makes a huge difference to use the correct paint in a damp environment.

Condensation itself is a function of the air conditions (temperature and relative humidity ie dew point) and surface temperatures. All surfaces should be comfortably above the dew point to prevent mold. You can use a hygrometer to measure the air, and an infrared thermometer to measure surface temperatures.

[esperent]

Absolutely but one thing about living in rented accommodation - you rarely get to choose the paint.

I agree that a dehumidifier helps but you basically need one in every room. Where I live you can easily take out 10 liters a day from every room during the humid season (which is the maximum capacity of the machine I rented).