Plaster finish is rough

hardya1

New Member
We have had a dpc done. Following dpc a special waterproofing rendering onto brick then regular plastering on that and the rest of the room skimmed to match as were told verbally paper after 12 months, paint after 6 weeks.

However on some walls there are deposits appearing. Surveyor visited and looked and said small print says paint after upto 9 months. Said sand off the deposits (salt?) as they appear over a period of up to 9 months, when deposits stop, paint.

We were definitely not told 9 months as the whole conversation was to get the rest of the room skimmed (old property walls) so that we could decorate by painting the whole room after 6 weeks rather than 12 months to paper.

The thing is where we are doing this little bit of light sanding off of the salts the walls (other rooms as well) are really rough with little rough bits showing through, compared to the other skimmed walls, and this roughness is not the loose salts that we are sanding off.

We are told that when it's dried it will be like the nice skimmed bits but looking at it, I very much doubt the roughness (not the surface salts) is going to go away compared to the regular walls, even if we wait 9 months and the surveyor said just one of the three walls was already close to dry.

I'm concerned that when painting, this part of the wall will "look" as bad as when the paper on had damp. It will "look" rough not smooth, even if it's no longer damp and I don't want to wait 9 months to discover it's actually just too rough.

As we sand a little (as instructed) a VERY think layer seems to come off gradually making it rougher than it already was to begin with.

Anyone any ideas / advice why this section of wall should be rough and what the best thing to do might be? We'd like to paint soon on the wall the the surveyor said of the 3 is very almost dry.
 

stuart23

Private Member
We have had a dpc done. Following dpc a special waterproofing rendering onto brick then regular plastering on that and the rest of the room skimmed to match as were told verbally paper after 12 months, paint after 6 weeks.

However on some walls there are deposits appearing. Surveyor visited and looked and said small print says paint after upto 9 months. Said sand off the deposits (salt?) as they appear over a period of up to 9 months, when deposits stop, paint.

We were definitely not told 9 months as the whole conversation was to get the rest of the room skimmed (old property walls) so that we could decorate by painting the whole room after 6 weeks rather than 12 months to paper.

The thing is where we are doing this little bit of light sanding off of the salts the walls (other rooms as well) are really rough with little rough bits showing through, compared to the other skimmed walls, and this roughness is not the loose salts that we are sanding off.

We are told that when it's dried it will be like the nice skimmed bits but looking at it, I very much doubt the roughness (not the surface salts) is going to go away compared to the regular walls, even if we wait 9 months and the surveyor said just one of the three walls was already close to dry.

I'm concerned that when painting, this part of the wall will "look" as bad as when the paper on had damp. It will "look" rough not smooth, even if it's no longer damp and I don't want to wait 9 months to discover it's actually just too rough.

As we sand a little (as instructed) a VERY think layer seems to come off gradually making it rougher than it already was to begin with.

Anyone any ideas / advice why this section of wall should be rough and what the best thing to do might be? We'd like to paint soon on the wall the the surveyor said of the 3 is very almost dry.
Pictures would help
 

Tinytom

Well-Known Member
Looks like it’s multi that’s had too much water on it too soon and it’s gone gritty, then maybe not had a final trowel to polish the surface. If your still getting salt through the damp proofing hasn’t been carried out correctly
 

johniosaif

Private Member
Advice to sand it is wrong ,lightly brush off effervescent deposits, a dehumidifier in the room and light heat should encourage it to dry properly, it's probably water that's sandwiched in the wall and is coming out on the inside (is the outside rendered or underground?) what were the walls like when they removed the old plaster ? If the were soaking ,the should of been left to dry out before been plastered , ask them for the spec that they worked to, ( they will probably lie ) you can only either wait and see or force them to redo , it's not a nice situation for you ,hopefully it sorts itself
 

hardya1

New Member
Outside is brick and recently thermotek.

Didn't get to see the inside of the brick, it was never said prior to work that at the point of the exposed brick there was a decision point which might lead to a wait.

Three rooms, one wall in each. One wall is producing a lot of salt, the other two very little. All three walls upto 1.5m are rough however, making painting after 6 weeks a concern. Now at 5 weeks.

Told to lightly sand not brush. Told salt is normal for up to 9 months.

I have only paid half, so may have some leverage. Wonder if it's worth paying for written opinion.

Thing is, maybe it's my profession / background, but dpc analysis, diagnosis and solution seems to be so random and opinion based that one is hard pressed to achieve any kind of clarity, agreement.

In the end dpc means we came to your house and did stuff and said it's right.
 

johniosaif

Private Member
Outside is brick and recently thermotek.

Didn't get to see the inside of the brick, it was never said prior to work that at the point of the exposed brick there was a decision point which might lead to a wait.

Three rooms, one wall in each. One wall is producing a lot of salt, the other two very little. All three walls upto 1.5m are rough however, making painting after 6 weeks a concern. Now at 5 weeks.

Told to lightly sand not brush. Told salt is normal for up to 9 months.

I have only paid half, so may have some leverage. Wonder if it's worth paying for written opinion.

Thing is, maybe it's my profession / background, but dpc analysis, diagnosis and solution seems to be so random and opinion based that one is hard pressed to achieve any kind of clarity, agreement.

In the end dpc means we came to your house and did stuff and said it's right.
Damp proof work is smoke and mirrors , like second car salesmen of the building industry , without seeing the wall after it been hacked off of its render , without knowing what mix they applied ,how many coats etc and what additives they used it's impossible to say anything with clarity , I wouldn't be inclined to pay up at this stage . Is there ventilation in the room constantly? What I did with my external walls was to add marmox board which is waterproof,it also stops the wall from been a cold wall ,it's also skimmable , might be a thought/ plan going forward
 

carlos

Private Member
Damp proof work is smoke and mirrors , like second car salesmen of the building industry , without seeing the wall after it been hacked off of its render , without knowing what mix they applied ,how many coats etc and what additives they used it's impossible to say anything with clarity , I wouldn't be inclined to pay up at this stage . Is there ventilation in the room constantly? What I did with my external walls was to add marmox board which is waterproof,it also stops the wall from been a cold wall ,it's also skimmable , might be a thought/ plan going forward
Spot on.




Sent from my iPhone using Tapatalk
 

Arti

Well-Known Member
salts are just the wall drying out but sanding it is gonna wreck the skim. just brush them off till it stops forming. whether you want to wait 9 months or not its just tough im afraid. the drying out period is just a guide. i tell customers 3 months before painting, some say 6 weeks blah blah blah. it just takes as long as it takes in my experience. we all have our opinions on this subject and some just tend to agree to disagree
 

flynnyman

Well-Known Member
salts are just the wall drying out but sanding it is gonna wreck the skim. just brush them off till it stops. whether you want to wait 9 months or not its just tough im afraid. the drying out period is just a guide. i tell customers 3 months before painting, some say 6 weeks blah blah blah. it just takes as long as it takes in my experience. we all have our opinions on this subject and some just tend to agree to disagree
It's best to wait before rendering then brush off and use a salt nutriliser but some people don't want to wait so like you say brush off with a soft brush.
 
Last edited:
Top