Damp proofing problems

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Gazmonster

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Hi guys,

I recently done a damp proofing job on an external stone wall that was showing signs of damp showing thorough.

Its gone a bit tits up tbh, the wall has been painted by the customer and now its got a load of efflorescence and is damp at the bottom of the wall. The original render was hacked off 1m up and sand/cement with a shite load of sbr was put back on and skimmed up. I never encountered this before so im a bit stuck as to how to cure it? Would a good coat of bitumen with carlite solve it or cause more issues?

Like i said im stuck on this one so im calling on the vast knowledge base of you chaps
 
Hack it off up to 1.2 2 coats of a decent tanking slurry 5:1 s & c with a decent waterproofer and salt inhibitor skim away
 
FreeD said:
Wheres the water coming from...is there pressure?
Click to expand...

Seems to be a fair amount of damp on the face of the skirting and underlay is a bit wet up to 6" out from the wall. The wall itself is wet about a foot up to the extent that the paint has gone soggy. I have no idea where the damp is coming from as the ground level outside is slightly lower .
 
Damp on face of skirting? so is that condensation that has run down the wall over the skirting onto the underlay? What ratio mix did you use with SBR?
 
5:1 sand cement with about 500ml sbr in each mix, muck stank of sbr. Customer says it wasnt like it before? I think i might lash a load of bitumin over the whole lot, carlite over it then skim it again. Gotta try and keep the cost down as it will be coming out of my own pocket this time and i didnt allow for **** ups :(
 
That mix is to weak m8, should be 3.1.

Where are you in Somerset, got a couple of m8s down that way who might be able to have a look?

Its hard to advise seeing it.
 
Gazmonster said:
Hi guys,

I recently done a damp proofing job on an external stone wall that was showing signs of damp showing thorough.

Its gone a bit tits up tbh, the wall has been painted by the customer and now its got a load of efflorescence and is damp at the bottom of the wall. The original render was hacked off 1m up and sand/cement with a shite load of sbr was put back on and skimmed up. I never encountered this before so im a bit stuck as to how to cure it? Would a good coat of bitumen with carlite solve it or cause more issues?

Like i said im stuck on this one so im calling on the vast knowledge base of you chaps
Click to expand...
Did You inject the stone gazza or just hack off and re-render?? Did you kill the salt before you re-rendered?? I only use SBR in the slurry coat
Like Freed says its hard to say with out some pic's marra
 
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that sounds a lot of sbr in the mix mate,would have gone with waterproofer myself.would have gone down the route of hacking off the render upto 1.2 as stated,then liquid damproof injection.make sure all is dry before sbr slurry,then 4:1 washed sharp n cement(with waterproofer).when dry skim with multi.
 
You need some pics mt, i had a job where this was happenning, it turned out to be a pipe in the floor, and the dry walls were soaking up then coming out and back down over the plaster and skirtings.
 
Gazmonster said:
Hi guys,

I recently done a damp proofing job on an external stone wall that was showing signs of damp showing thorough.

Its gone a bit tits up tbh, the wall has been painted by the customer and now its got a load of efflorescence and is damp at the bottom of the wall. The original render was hacked off 1m up and sand/cement with a shite load of sbr was put back on and skimmed up. I never encountered this before so im a bit stuck as to how to cure it? Would a good coat of bitumen with carlite solve it or cause more issues?

Like i said im stuck on this one so im calling on the vast knowledge base of you chaps
Click to expand...


FFS

Are you lot thick ?

The CARLITE (browning maybe) looks damp

:RpS_cursing:
 
The carlite aint on the wall yet, that was a poss fix i was thinking of using over a 2 coat bitumin. I cant get back in there now til week starting 27th feb so cant get any pics yet. The carpets are up and away from the wall now and the customer is leaving some windows open to allow airflow through the building (old coach house) I cant use salt neutralizer on the wall as its been painted. The basic story is that she needed it done asap as she rent the coach house out and i had about 4 days to get it done so she could paint it ready for the people to arrive, she told me she saw salt showing through pretty quick but had to get on and paint it as it was booked in to be let for a week. If i was told before it was painted i could have possibly done something about it but thats life and now i gotta sort it. Cheers for the input so far chaps. I had to sharpen the pencil on this one as it was a local customer whom ive done work for before and keeping the locals happy is a big thing for me living in the sticks, so i couldnt leave alot of room for the possibility of throwing another 300 quids worth of materials at it. Would bitumen, lapped over the floor by a foot coated with bonding then skimmed hold it back or is gypsum in this situation asking for trouble?
 
Looks like i need to try and get back in for more investigations then. She says it wasnt ever that bad before so i may have inadvertently disturbed a hidden demon. Not liking this one much, could end up costing me a fair wedge. I seems to only be wet at the bottom with salts the rest of the way up. I'll get in and strip the paint and have a poke about to see what i can find. Could well be rising as the chipboard floor was a bit rotten and damp where it touched the wall before i started.
 
Its a lounge in a 2 story coach house that get rented out as a holiday let, people in for a week then maybe no-one in there for a few weeks or more til the next lot arrive. This one is doing me nut in tbh now lol
 
Gazmonster said:
Hi guys,

I recently done a damp proofing job on an external stone wall that was showing signs of damp showing thorough.

Its gone a bit tits up tbh, the wall has been painted by the customer and now its got a load of efflorescence and is damp at the bottom of the wall. The original render was hacked off 1m up and sand/cement with a shite load of sbr was put back on and skimmed up. I never encountered this before so im a bit stuck as to how to cure it? Would a good coat of bitumen with carlite solve it or cause more issues?

Like i said im stuck on this one so im calling on the vast knowledge base of you chaps
Click to expand...
eems to be a fair amount of damp on the face of the skirting and underlay is a bit wet up to 6" out from the wall. The wall itself is wet about a foot up to the extent that the paint has gone soggy. I have no idea where the damp is coming from as the ground level outside is slightly lower .


As others have said:
the moisture is likely to be condensation. Sand and cement render being a poor insulator promotes the formation of condensation this would be noticeable if your rendering replaced a previous covering that was a better insulator. Is the affected room a kitchen?
.
the render has failed, either because there is salts within it (less likely but note the importance of washed sand) or salts within the wall are migrating through it.
.
the presence of salts indicate your render as being ineffective but as you put lots of SBR in your render mix a better understanding of what the client painted onto the wall is worth investigating. Had the render dried out completely prior to painting?
.
And the floor wall junction is always a weak point that may allow water migrate into the house if the base of the wall is saturated by penetrating or rising dampness. However condensation will form on the floor in a similar manner.
In your defence you might point out to the client that you are relatively innocent in respect of condensation, completely if you replaced a sand and cement render with another sand and cement render. And that the paint problem if a water based paint, which you would expect on a wall may be completely a failure due to condensation. As for efflorescence I would investigate the powers of SBR I would have guessed that this would be adequate to hold back any salts in the wall, but you guys are more knowledgeable than me about this, what’s it say on the container? Was you sand reasonably clean and free from salts or did you dig it up from the beach?
Regards Steve
 
If she is after a quick fix for renting out the place, you could try some damp seal paint, then paint on top to match room once dry.
How much of the room is affected? if it's only a small area it'll only cost you £10-£15 for a tin of damp seal.
And it does work I've used it a few times :RpS_thumbup:
 
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Gazmonster said:
Looks like i need to try and get back in for more investigations then. She says it wasnt ever that bad before so i may have inadvertently disturbed a hidden demon. Not liking this one much, could end up costing me a fair wedge. I seems to only be wet at the bottom with salts the rest of the way up. I'll get in and strip the paint and have a poke about to see what i can find. Could well be rising as the chipboard floor was a bit rotten and damp where it touched the wall before i started.
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You can still get salts as the wall is drying out gazza. The rule of thumb is it takes 1 month per inch of wall to dry out and if its a stone wall its could take quite a while. They should only have painted the wall with non vynyl paint so the wall can still dry out.But i would have still waited 3-4 months before painting it
 
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Get some vents in the wall, then build a stud wall in front of it with a couple of vents in that too. That will give her a wall that she can paint after 4 days, cos to be honest I don't know how she was able to paint over your work after 4 days, no way would it be dry enough.
 
Artisan998 said:
You can still get salts as the wall is drying out gazza. The rule of thumb is it takes 1 month per inch of wall to dry out and if its a stone wall its could take quite a while. They should only have painted the wall with non vynyl paint so the wall can still dry out.But i would have still waited 3-4 months before painting it
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Just asked them how is was prepared before painting and with what paint and it was pva'd then painted with a vinal paint so its prob held it all in and not allowed it to dry out. I'll get down there and try to strip all the paint off the areas i done and hit it with salt neutralizer a few times and tell them to leave it alone :RpS_thumbup:

Nice one chaps, i knew i could rely on you lot to help:RpS_thumbsup:
 
Pva'd before painting!! ffs some people ain't got a clue :RpS_laugh:
And she used vinyl emulsion over still drying out plaster!!
So why is this your problem to sort out Gaz??
She has painted it to early that's not your fault is it??
 
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