Black smudges appearing on hallway walls and ceiling before repainting

[fiorentina]

We’ve just moved into a new property (1950s) and started decorating. It’s not a complete renovation as largely up to date.

I’ve noticed as I wiped down the walls and ceiling in the hallway and cloakroom to clean and prep that black smudges are appearing on the white paint. It’s clearly (very evenly) in something. There’s no sign of mould around the house, it wasn’t previously freshly painted to hide anything. We are wondering if it’s soot? Any other suggestions and also whether we need additional prep before painting. Thank you.

Is it anywhere near a chimney or heating appliance?

Thanks for your response.
There’s a log burner in the adjacent sitting room and it’s next to the kitchen which was incredibly grubby/greasy when we moved in despite it being relatively new. There were candles burning every time we visited so I suppose if the vendors were big fans of candles that could contribute?

Maybe. Have you had the burner serviced/swept since you moved in?
That should help rule out anything to do with that.

Thank you for your suggestions. We haven’t, but we’ve been here only 3 weeks and not used it yet. It was swept within the last 12 months - paperwork supplied by the vendor but having had a log burner that occasionally really smoked at our old house at the beginning of the season when the chimney was too cold, maybe it is that.

I’ve cracked on painting for now and will monitor the state of freshly painted rooms.

We have this too - I think it’s in the old plaster. I reckon the best thing is to seal it well before painting over it again.

Ah interesting, thank you for sharing.
So far I’ve only decorated the loo, so will keep an eye out for any smudges returning there.

Maybe this is why the house is painted 50 shades of grey! Ceilings aren’t though..