Efflorescence on internal wall, how to get rid of it?

[Nige F]

Ah I see. Yeah the shut off is further down at knee level in the boxing if I remember correctly

It wouldn't be a bad idea to fit a purpose made plastic cover in the boxing - not for you as you know it's there, but as an obvious and convenient point in the house

 

[ted456]

Because your valve is hidden by the boxing-in its not accessible. A gas safe inspection might call it NCS (not to current standard) or even condemn the installation?
Do you know if its got a fixed handle or there's just a cut-off valve plug that requires a loose lever handle to even move it? A loose lever must be present by the valve.
In that tight space I'd suspect your's is a handleless plug valve?
You'll have to remove the cover of the boxing to examine the plaster behind the boxing so why not check the Isolator and see if it has a handle and that the valve works?
Best, safe practice would be an immediately accessible and observable modern fixed handle valve.

 

[robodelfy]

Because your valve is hidden by the boxing-in its not accessible. A gas safe inspection might call it NCS (not to current standard) or even condemn the installation?
Do you know if its got a fixed handle or there's just a cut-off valve plug that requires a loose lever handle to even move it? A loose lever must be present by the valve.
In that tight space I'd suspect your's is a handleless plug valve?
You'll have to remove the cover of the boxing to examine the plaster behind the boxing so why not check the Isolator and see if it has a handle and that the valve works?
Best, safe practice would be an immediately accessible and observable modern fixed handle valve.

Sorry I should have been clearer. So down at kneee level there is a hole in the box, about 20cm x 15cm. There is a lever/handle to turn the gas off there. The handle is always on it

Is that ok?

 

[Nige F]

Call your gas supplier , Free of Charge - it's their valve - and bobasd's your uncle you might even get a smart meter so you don't need a ladder to read it.

 

[dontbelieveawordofit]

Call your gas supplier , Free of Charge - it's their valve - and bobasd's your uncle you might even get a smart meter so you don't need a ladder to read it.

. did someone mention bob

 

[Nige F]

.I just reealized I made a typo. I meant Bob's your uncle No way to vinndicate myself

 

[mrrusty]

Based on experience in my own house, it's salts in the wall. Victorian houses which had lots of coal fires will have salts in them all caused by combustion products reacting with, in particular, lime based materials. I still have a little battle going on with salts around the side walls in my fireplace - I know the only ultimate remedy is to chop out all the salt laden bricks and rebuild. Interestingly, when we were doing the refurb we also had some salt patches showing up where the dabs were on some newly boarded walls - the wet in the dabs drew the salts through the PB. However these did disappear once we got heating on.

Based on my own experience, I would strip the wall and re-board using a foam board adhesive rather than a wet board adhesive to secure the boards. The foam will insulate the boards from the salt-laden bricks.

 

[robodelfy]

Based on experience in my own house, it's salts in the wall. Victorian houses which had lots of coal fires will have salts in them all caused by combustion products reacting with, in particular, lime based materials. I still have a little battle going on with salts around the side walls in my fireplace - I know the only ultimate remedy is to chop out all the salt laden bricks and rebuild. Interestingly, when we were doing the refurb we also had some salt patches showing up where the dabs were on some newly boarded walls - the wet in the dabs drew the salts through the PB. However these did disappear once we got heating on.

Based on my own experience, I would strip the wall and re-board using a foam board adhesive rather than a wet board adhesive to secure the boards. The foam will insulate the boards from the salt-laden bricks.

Thanks, you said you know the only remedy is to take out the bricks and re build. But then you said to just take of the plaster and use foam board

Do you think it's enough to just remove the plaster as someone earlier said and treat the bricks

I just don't want to rip my house apart more right now unless I'm confident it will work!

 

[mrrusty]

I was talking specifically about my fireplace where I know the bricks have a high salt loading, and it's not practical to use plasterboard and foam in a fireplace. In my fireplace, I could chop out the old brick and use some concrete blocks, but you wouldn't want to do that on a party wall!

I took a whole edwardian house back to bare brick recently and drylined all walls (except for a couple of internal bedroom walls where the original plaster was OK, and a couple of chimney breasts). Walls where we used insulated PB, or PB with foam adhesive have been fine. Internal walls where used wet adhesive have also been fine except in one room where we know a coal fire burned every day for 110 years pretty much. In that room we found when we plasterboarded that in a couple of places the dabs showed through as "damp" patches that never dried initially, and a fine surface salt appeared - therefore it was pretty obvious the wetness in the dabs had drawn salts from the wall. Fortunately everywhere except around the sides of the fireplace has disappeared with central heating. We are slowly beating the fireplace, helped a lot when we got all the chimneys capped or cowled.

I'm not sure any surface treatment to the bricks will do very much, but I am confident that if you use a foam board adhesive like "Instastik" to fix new plasterboards and then re-skim, the salts will not cross the foam barrier. - to be clear this is ordinary plasterboard fixed with a foam adhesive, not a foam board!

https://www.youtube.com/watch?time_continue=64&v=fA1TFVJKaPQ&feature=emb_logo

 

[ted456]

OP,
there's no need for cutting out bricks - none at all.
Dont go pulling out the wall in a hallway - you need the space.
You were advised last wed to hack off the whole wall - if you do that and then post a pic you can be helped further with a simple, cheap and effective way of dealing with the damp.

 

[dontbelieveawordofit]

I could chop out the old brick and use some concrete blocks

or you could replaster it with salt inhibitor . like a pro.

 

[dontbelieveawordofit]

i wouldnt hack anything off, it’s an internal wall with no reasonable possibility or evidence of rising falling or penetrating damp .
scrape the salts back wash the wall and board it .