Help: flaking paintwork / damp on concrete walls

[Fizzipop]

Seeking advice for tackling some decoration issues in a mid-rise (8-storey) block.

The walls are a mix of brick and concrete construction from late 60s/early 70s. The brick parts are fine, but the concrete parts are thinner and colder: every winter, the wall gets mouldy, and the paint discolours and bubbles/flakes off, both from the wall and the adjacent ceiling. I can't tell if this is penetrating damp or interstitial condensation, because it gets going when a) it's been raining a lot AND b) when there's a cold snap.

It's in a tower block so the exterior walls are inaccessible. Only option is to deal with it from the inside.

What's the best permanent way to tackle this? Are we talking a couple of damp-proof paint base coats topped with anti-mould paint, or should I be looking at thermal insulation boards? Any thoughts welcomed!

 

[footprints]

A rule of thumb test is to dry the wall and tape a section of clear plastic flat to it, if it gets damp underneath it's likely to be damp, if the underside stays dry and the surface of the plastic gets wet it is condensation.
As an aside we had a rental flat first two occupiers had no problems the next set had exactly the same trouble as you. All about lifestyle I guess, shower, cooking in the morning both out all day, windows closed. Maybe they got a bit more steamy at nights too! We supplied a dehumidifier totally cured it!

 

[Fizzipop]

A rule of thumb test is to dry the wall and tape a section of clear plastic flat to it, if it gets damp underneath it's likely to be damp, if the underside stays dry and the surface of the plastic gets wet it is condensation.
As an aside we had a rental flat first two occupiers had no problems the next set had exactly the same trouble as you. All about lifestyle I guess, shower, cooking in the morning both out all day, windows closed. Maybe they got a bit more steamy at nights too! We supplied a dehumidifier totally cured it!

That's genius! Will dry a patch and try the plastic trick. And guess I'll be shopping for a dehumidifier this weekend — much better shout than messing around with insulation Thank you!

 

[opps]

I suspect that it may be condensation. It is likely to appear in corners of exterior walls. The air circulating around kinda skips corners as it arcs around them.