Small spots on chimney wall

[ed32]

Hi there. After the recent rain we have noticed these small spots appearing on the wall around the fireplace (clear but not in use, chimney cap on with vent, chimney balloon inside for draft protection), slightly worse in places, and does go on to the window on the right of this photo.

On googling it sounds like salts potentially, but unsure. Any thoughts/suggestions welcome!

Edited to add more photos:
- full wall highlighting where the spots are most concentrated (they are still there but much more sporadic further to the edges)
- photo of the spots nearer the window side
- photos of outside wall

 

[Wayners]

Not sure about the balloon.
You may need a steady flow of air up chimney.
Very little damp course in all chimneys because of heat so they get damp with no fire to dry out.
Read up.
Get advice from damp company if you can't sort yourself

 

[ree]

OP,
Please show a pic of the whole chimney breast - skirting to ceiling plus any hearth?
And pics of the continuing damage to the window on the right?
And a pic showing the outside of the chimney breast back wall?
If you have a balloon in the flue then the flue wont do much venting.
Was the flue swept before becoming redundant?
Have you closely examined any other c/breasts for spots or bubbles?

 

[ed32]

OP,
Please show a pic of the whole chimney breast - skirting to ceiling plus any hearth?
And pics of the continuing damage to the window on the right?
And a pic showing the outside of the chimney breast back wall?
If you have a balloon in the flue then the flue wont do much venting.
Was the flue swept before becoming redundant?
Have you closely examined any other c/breasts for spots or bubbles?

Thanks, I've added more photos as requested.

The flue swept before being taken out of use but it was some time ago now, a few years.

There's no bubbles around any of these spots or on this whole wall. And nothing similar on other chimney areas of boarded up (with vents) other fireplaces.

 

[^woody^]

They are indicative of mould spotting or a reaction within the paint to something left on the walls before painting. Either way, bought on by internal condensation not external water penetration.

You will need a coat of blocking paint, such as from Zinsser (one for grease may be appropriate such as Zinsser 123), and then you can repaint the whole wall.

 

[ree]

OP,
Thanks for the pics. However, they dont show anything of significance.
Painter's forum might be your best next step for advice?

 

[ed32]

Thanks for the feedback, I'll have a look at getting it posted there.