Crystalline deposit on plastered intenal wall

[mike25225]

Hi,
Am seeking information regarding cause of a salt-like deposit that appeared on the surface of a plastered internal (kitchen) wall. This developed into larger "bumps" - some hollow and some solid.
It is NOT a newly-plastered wall, and the problem only affects it up to about 4 foot from floor.
There is no sign of damp, and it appeared to be chemical in origin, but would really like to know what it may be.

Thanks in anticipation of some enlightenment........

Mike.

 

[noseall]

efflorescent salt crystals, usually as a by-product of a wet wall that has dried out.

 

[mike25225]

Thanks for that. Is remedy to simply sand down and repaint - or is there any other required treatment?
There is no sign of residual dampness now.

Thanks and regards,

Mike.

 

[noseall]

yep, just sand off the residue. it's normal and harmless (unless you're a coat of paint), just a nuisance that's all.

 

[FredFlintstone]

yep, just sand off the residue. it's normal and harmless (unless you're a coat of paint), just a nuisance that's all.

Hi Noseall,

Aren't the salts hygroscopic though which means they attract water so the whole lot needs to be taken back to brick and re-done with 3/1 s/c with RendaProof added? Or is that just hype made up by damp proof companies to make more money?

Regards

Fred

 

[noseall]

not all salts are hygroscopic.

all masonry contains salts in some degree and is usually 'sweated out' after being saturated with water.

if this were the case a heck of a lot of winter new builds would need re-plastering from top to bottom.

 

[mike25225]

Hi,
Going back to my original query - I have since removed the paint and applied a fungicide (mould cleaner - is that the same thing?) - but within 24-48 hours a growth has re-appeared. It has a thin pale hair-like appearance. Not sure if photos can be attached here, but can send one direct if it would help someone provide an answer.
Thanks and regards,
Mike.

 

[JohnD]

we don't think it's mould, we think its efflorescence (look it up). it will come out each time the wall gets wet with water and subsequently dries out. just brush it off.

Don't try to wash it off with water as the crystals will just dissolve in the water and soak into the wall again.

//www.diynot.com/forums/viewtopic.php?t=73320

p.s. kitchen walls often get wet from leaking pipes (can be under the floor), overflowing sinks or even excessive wet mopping. You have to cure the source of the problem. once the wall is dry and stays dry it wil stop coming out.

 

[mike25225]

Thanks for advice - especially from Noseall and JohnD. However, the problem continues, and I would like to offer a couple of photos of the affected area, for your further opinions.
I've not been able to sus out how to attach photos here, but if you let me have your e-mail addresses, I can mail you jpegs direct.
Thanks,
Mike.

 

[FredFlintstone]

Mike,

If you wanna e-mail them to me I'll post them up for you.

E-mail's in my profile.

Regards

Fred

 

[JohnD]

//www.diynot.com/forums/viewtopic.php?t=73320

 

[FredFlintstone]

Here you go Mike.

Regards

Fred

 

[noseall]

you seem to have a problem there!

that looks like it may be caused by something more sinister than environmental damp. are there any water pipe chases up that wall?

 

[suziflick]

Hi did you have any success in getting rid of salty deposits on your kitchen wall? I have similar problem on bedroom wall.