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adhibs
07-06-2018, 04:06 PM
Has anybody on here dealt with this? From what I've read it looks like the area needs re-plastered, but is their any other options? I've came across this https://www.permagard.co.uk/salt-neutraliser-5-litre , although no idea if it would work. The affected areas only around 150mm x 100mm, and has barely worsened over the last couple years.

speedy_gonzales
07-06-2018, 05:36 PM
I'm not an expert so I might be wrong but do you not normally suffer from this if there's a leak or water ingress from something like poor pointing/grouting. If so, has that been remedied first?

adhibs
07-06-2018, 06:24 PM
I'm not an expert so I might be wrong but do you not normally suffer from this if there's a leak or water ingress from something like poor pointing/grouting. If so, has that been remedied first?

Think its left over salts from when the chimney was operational. Its an internal wall also so isnt subject to other external inputs.

beensaidbefore
07-06-2018, 07:38 PM
Think its left over salts from when the chimney was operational. Its an internal wall also so isnt subject to other external inputs.

Could there be water ingress from the chimney? Do you have access to the roof? If so pop your head up and look to see the chimney is looking ok at the top.

You could also get a damp meter to check the affected area, if there is no dampness you should probably be fine. Try sanding it down and painting of its dry.

adhibs
08-06-2018, 09:47 AM
Could there be water ingress from the chimney? Do you have access to the roof? If so pop your head up and look to see the chimney is looking ok at the top.

You could also get a damp meter to check the affected area, if there is no dampness you should probably be fine. Try sanding it down and painting of its dry.

Im on a ground floor flat with a fireplace in place of the old chimney so no access to check unfortunately. I might try the sanding and giving it a coat of eggshell to see if it holds.

speedy_gonzales
08-06-2018, 02:53 PM
My understanding is it takes a small amount of water traveling through to cause the minerals/salts to bloom.
Hopefully it's a historical case and you have no further dramas but chimneys are notorious for leaking water, usually because the pointing has failed with time and in older buildings it can be difficult to weatherproof with traditional methods.

adhibs
08-06-2018, 03:05 PM
My understanding is it takes a small amount of water traveling through to cause the minerals/salts to bloom.
Hopefully it's a historical case and you have no further dramas but chimneys are notorious for leaking water, usually because the pointing has failed with time and in older buildings it can be difficult to weatherproof with traditional methods.

Hopefully thats not the case as it sounds like a pretty big job. From other conversations/research, ive heard its salts existing in the plaster reacting with humidity in room, and thats how theres no sign of damage on the part of the wall previously protected by the skirting.

I contacted the company offering the salt neutralizer and they said it was suitable but not a guranteed solution. I may give it a go as its pretty cheap and a lot less hassle than getting the area replastered.