Paint falling off

[HumanAstronomer3194]

The paint in my parents kitchen is falling off the wall and I'm not 100% sure why. Last year there was a lot of mold growth on the interior block walls (ie not an exterior wall) and the paint was falling off the walls. I put this down to the fact my parents refuse to turn on the heating and use portable gas heater instead so when they are cooking the first cold wall moisture hits will be these walls thus causing condensation.

My father got some product from the local paint shop in a none labelled bottle but it smelled a lot like bleach and the drops the landed on my black jeans turned white. While my parents where away I painted the whole kitchen with this product and a few weeks later the room was repainted. Now one year later the paint is coming off the walls again but this time way more easily and falling like dust. I was able to take off a lot of the paint just using a kitchen brush.

Now I'm not sure why. Is it because before painting we didn't wash the walls down again or is it something else?

Original mold

Half and half view while paint this unknown product

Vs One year later

After I brushed the wall and used a scraper

 

[Wayners]

They are creating high humidity and the moisture is settling on the cold surfaces as condensation.
Opening windows or putting the heating on won't fix it.
You need to read up and understand what's happening.
Reduce the amount of moisture created where possible.
Run a dehumidifier ( we run two every evening)
Vent when cooking.
Don't dry washing in the house without a dehumidifier.
Just do what your can to reduce the humidity

 

[HumanAstronomer3194]

Thanks @Wayners. I had put them tablet dehumidifiers into the kitchen and while it soaks up a lot of moisture I don't think its enough.

I did find out my father bought a dehumidifier from Aldi a while ago that is still in the box. I will put that in the kitchen and monitor the wall over the winter.

 

[Wayners]

Those tablets are useless. They pull less in a month than a good dehumidifier will pull out the air in a couple of hours.
I bought some to try and binned it when I realised how useless they are