Efflorescence/Damp?? Help

[Joannaold]

Hello

I'm new here... Being cheeky and looking for some advice/ different opinions as I'm currently stuck with what to do.

My house has exposed brick fire place/ chimney in living room.
when re-painting the bottom half we have experienced horrible staining yellow brown and black and also powdery crumbling.
I can't work out if it's damp or some kind of salts coming through the brick. Any help would be greatly appreciated. The next thing I was going to try was sandex stabilisation solution and then re-paint with sandex textured paint?

 

[tony1851]

It's salts from coal-burning which have leached into the brickwork, possibly combined with some rising damp if it's near the bottom.
There are products such as Polycell Stainstop, but don't know how effective it would be for heavy deposits.

 

[Burnerman]

A mixture of sulphur and soot, as Tony says.....Zinsser paints do an effective stain block, but there is dampness there.
Is the fire still working?
John

 

[ree]

Nothing will block or stop the effect of the (hygroscopic) salts that have come thro the brickwork as a chemical liquid (deliquescence). The salts come from the soot in the chimney breast flue - a flue that needs sweeping, and to sweep the flue the fire needs removing.

Is the fire gas or elec and is it active or redundant?

The affected plaster on the c/breast (& the skirting boards) need removing back to bare brickwork - as high as needed plus 300mm.

Why not post pics of the whole chimney breast and a metre or so of the return walls? A pic of the chimney stack would also help.

If you roll the carpet back a little you might see damage to the flooring?

Any other c/breasts in the house are most probably in an unswept sooty similar condition - all flues must be vented top and bottom.

If that back wall is an outside wall then go out and examine it for sooty stains in the bricks or render.

 

[Joannaold]

Hi Tony, Burnerman and Ree.

Thank you all for your messages.

All fires have been removed, I just have a little electric plug in one that sits in there but just for a feature, never actually switch it on.

 

[Joannaold]

Hit reply before finishing the message then!

We have solid floors and no other sign of damp anywhere?

I really just wanted to paint the brick but sounds like I have an underlying issue

I'm thinking I maybe need someone to come and check the chimney/ roof as I don't know if chimney is sealed off or capped? If that makes a difference?

I will look into removing the plaster also.

Thanks

 

[ree]

I dont understand - what is showing in pic 1. - a fire surround?

Dont attempt any work while in the vicinity of live elec or gas.

If you provide the pics perhaps we can help you further before you start randomly and maybe expensively bringing in various people.

 

[Joannaold]

Hi

Sorry I'm not being clear I have attached another picture of the full wall.

It's an internal wall and our house is a mid terrace.

The fire place and chimney are all entact just the actual fires that are no longer there. I believe they have both been sealed internally.

Could it just be damp travelling down the chimney if it's not capped or sealed at the top? I will take a pic of the chimney/ roof tomorrow and upload.

Thanks again

 

[Burnerman]

Ideally, the redundant chimney should have some sort of ventilation at the bottom and top, just to let any air circulate....this is usually done with air bricks at the outside and it is sealed above the fire. If this is done, the chimney can be capped to prevent rain and birds etc becoming a nuisance.
In your case, and its only a guess, I think there is rising damp coming up through the hearth, and your slate slabs prevent it being visible under the fire - but it is appearing at the sides (the reveals.)
If you pull the carpet back, is there any sign of dampness there?
John

 

[ree]

Thank you for the pics.

Sooty penetration can be seen on the bare bricks esp. the brick arch and the wood ceiling coving.

If you remove the furniture and chattels from either side ofthe c/breast you could carefully examine the return party wall from skirting to ceiling - i suspect that there might be condensation somewhere?

Looking up inside the fireplace there might be a metal register plate - perhaps it will have a vent opening, perhaps not?

Besides removing all the c/breast plaster you will have to hack-off the fire place opening plaster and clean up the sooty brickwork that you will find there.

There is also the possibility of moisture coming up from the old hearth soil. Soil that acted as a filler and might act as a capillary path for the moisture?