Mysterious circles on paint work

[Luke Sanderson]

Hi guys,

Noticed these circles on the paint work all over the house. You might be able to see I've tried to wipe them off and made a bit of a mess. We do burn candles in the house and it seems the soot seems to collect on the wall in these areas. Does any one have any idea what is causing it??

 

[JohnD]

The wall is plasterboard attached to the bricks or blocks behind with blobs of fixing plaster. Where these blobs touch the plasterboard they cool it, so that humidity condensation, but also dust and as you say candle smoke sticks to the cold areas.

If you find that, when you try to sponge it off with detergent, the dirt smears, this is very typical. The dirt is extremely fine particles. Such marks are often seen in homes of smokers and people with coal or log fires. Candles are less common, but you usually see the smoke smear on the wall behind the candle, and the ceiling above.

I would expect the marks to be on external walls that are chilled by outdoor temperatures, not on internal walls that should be fairly warm.

I don't know a successful way to clean it off. Sugar soap will get most of it off so you can paint over the remaining smear.

 

[Luke Sanderson]

Thanks ever so much for that JohnD. Makes total sense. I wanted to know the cause before taking action. I'll sugar soap and paint and maybe ask my fiancée to burn a few less candles.

 

[JohnD]

tell her she can burn candles if she does the decorating.

And check the batteries in your fire detectors