Rising damp- how to treat?
Discussion
It sounds like efflorescence, (it's a word, honest) the white powder usually associated with damp, either rising or penetrating, which is what you will have to determine. These will sort out any rising damp and are more user friendly than the cream Dry rods Getting rid of the salty powder is more tricky and usually involves re-plastering with something like this Renovating plaster and all the mess that goes with it. As said, pics inside and outside near the affected area would help.
wolfracesonic said:
It sounds like efflorescence, (it's a word, honest) the white powder usually associated with damp, either rising or penetrating, which is what you will have to determine. These will sort out any rising damp and are more user friendly than the cream Dry rods Getting rid of the salty powder is more tricky and usually involves re-plastering with something like this Renovating plaster and all the mess that goes with it. As said, pics inside and outside near the affected area would help.
The dryzone people have a liquid that you can brush onto the wall to get rid of the salts. I think it allows one way breathing. They also have a dot and dab solution so that you can fit plasterboard on the same day as the treatments. I've not ordered ityet because they never answer the telephone, fkwits, lol.paulrockliffe said:
I think a lot of rising damp is actually penetrating damp combined with a bridged cavity. The cavity on my house has been blocked with bits of mortar and brick for the first metre, it's a relatively easy fix if you don't mind a bit of graft.
Rising damp product salesmen unsurprisingly find a lot of rising damp...Mattt said:
paulrockliffe said:
I think a lot of rising damp is actually penetrating damp combined with a bridged cavity. The cavity on my house has been blocked with bits of mortar and brick for the first metre, it's a relatively easy fix if you don't mind a bit of graft.
Rising damp product salesmen unsurprisingly find a lot of rising damp...Rising damp is very rare in the real world as opposed to the world of damp cure salesmen with their moisture meters. This guy talks sense
http://www.telegraph.co.uk/property/propertyadvice...
Have a look through the articles, he's done several on 'rising' damp.
http://www.telegraph.co.uk/property/propertyadvice...
Have a look through the articles, he's done several on 'rising' damp.
Because I'm working my way along the wall, removing every 4th brick and clearing it out at the rate of about one wheelbarrow full every metre.
The bottom is full of set lime mortar that has fallen in when the wall was built, fortunately this can be broken up with a lot of effort. On top of this there's lots of dust and dirt that appears to have disintegrated from the internal pointing over time. And interspersed amongst this and jammed at various points in the wall are bits of brick.
It's a job that's taking ages as after going at it for an entire day my hands need a couple of weeks to recover before going again.
The injected DPC was done at some point, I don't know when as it predates me living here. What's interesting is that it's a cavity wall, only the outer leaf is injected and the damp is on the inner leaf. So either the company thought it was a solid wall, but didn't drill far enough into it, or they thought the damp was rising on the outer leaf and then bridging a full cavity, but didn't clear the cavity. Or they were just taking the piss.
The bottom is full of set lime mortar that has fallen in when the wall was built, fortunately this can be broken up with a lot of effort. On top of this there's lots of dust and dirt that appears to have disintegrated from the internal pointing over time. And interspersed amongst this and jammed at various points in the wall are bits of brick.
It's a job that's taking ages as after going at it for an entire day my hands need a couple of weeks to recover before going again.
The injected DPC was done at some point, I don't know when as it predates me living here. What's interesting is that it's a cavity wall, only the outer leaf is injected and the damp is on the inner leaf. So either the company thought it was a solid wall, but didn't drill far enough into it, or they thought the damp was rising on the outer leaf and then bridging a full cavity, but didn't clear the cavity. Or they were just taking the piss.
moles said:
How old is your house?, our 1800's house has the cavity full all the way up to the upstairs floor as i took a brick out and dry dirt/sand poured out.
Mine is 1906. I've been told repeatedly on here that cavity walls didn't exist then, so you definitely can't have a cavity 
Are you sure it's full all the way up? Do you have a row of half bricks anywhere? I have one at first floor level, these are bricks that span the cavity and are also trapping another load of muck, but there's clear space between them.
Looks like the stones could be contributing. There looks like there is a membrane below the gravel so try pulling the stones away so the membrane is below the air brick all the way along that picture. Clean the air brick from outside. Can't see airbrick inside so has it been covered? Cold air and water coming through onto the internal wall meeting warm brick and causing more water. Try removing some plaster to uncover the air brick.
Is it gypsum plaster and modern paint? Try lime and breathable paint which will also help.
FFG
Is it gypsum plaster and modern paint? Try lime and breathable paint which will also help.
FFG
moles said:
How old is your house?, our 1800's house has the cavity full all the way up to the upstairs floor as i took a brick out and dry dirt/sand poured out.
Are you sure that's not the mortar from your second row of bricks in a non-cavity wall? 
Certainly our 1890 house doesn't have a cavity except for the 70's extension
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