Cost for sorting damp issue? (internal render + plaster)
Discussion
I have a small damp issue visible on one wall of my small terrace house. I had someone visit to advise on work today (which shockingly was exactly what i thought was required...). However, i'd like an opinion on what the work should approximately cost to get done.
What i need is a portion of the front wall (~5sq m) stripped back to the brickwork, rendered with waterproof covering, and plastered. Then externally there's a small bit of repointing to do (eg. 1sq m).
Does anyone have a thought on what that would cost to have done?
Also, would it matter if i get the pointing done straight away and before the internal work?
Thanks
What i need is a portion of the front wall (~5sq m) stripped back to the brickwork, rendered with waterproof covering, and plastered. Then externally there's a small bit of repointing to do (eg. 1sq m).
Does anyone have a thought on what that would cost to have done?
Also, would it matter if i get the pointing done straight away and before the internal work?
Thanks
I can't see that doing the pointing first will be a problem?
Have you actually identified and fixed the cause of the damp? I've always thought waterproof interior rendering was a bad solution if it's just to cover a problem as it doesn't really fix it and if anything drives the moisture to somewhere else.
Have you actually identified and fixed the cause of the damp? I've always thought waterproof interior rendering was a bad solution if it's just to cover a problem as it doesn't really fix it and if anything drives the moisture to somewhere else.
It's an old house without cavity walls. The damp patches on the wall are fairly high up, so it seems like penetrating damp. The wall is mostly stone bricks with a layer of normal brick work between floor levels. The stone has recent pointing, but the brickwork has visible holes. It seems that the water enters here and moves down the wall. Hence looking at sorting the pointing and then fixing the internal rendering/plaster.
Matt.. said:
The stone has recent pointing
That wouldn't have been done using cement rather than lime would it?The type of work they've quoted for won't resolve your damp issues and will cause bigger problems in the long term. Do not get them to do it - it'll be a waste of money and may cause irreparable damage to the house.
Cement repointing will be much harder than lime. If you try to scratch at it with the end of a screwdriver and compare it to that of the brickwork you'll likely find that there's a big difference in hardness between the two.
My guess at this stage is that the stone repointing has been done in cement. Tbh it's so rare these days that it gets done properly with lime that I can pretty much guarantee it's not. If it is cement, then moisture will struggle to evaporate, being forced now to evaporate from elsewhere which will be the stones (hard for it to do) or through the internal surfaces which is where I suspect the damp patch is coming from given your description - probably from a point slightly lower than the top of the external stonework below the brickwork.
If that's the case then repointing the brickwork isn't going to help. If the pointing is in poor condition then it still needs to be done to protect the mortar between the bricks but it must be done in lime to prevent spalling of the bricks. If the stonework has been repointed in cement then really that needs to be redone properly or the stonework will start to erode rapidly and the damp issues are only going to get worse as moisture levels continue to rise within the wall.
Period properties can't be treated like modern ones, and the use of modern materials on them leads to rapid degredation of the building and problems with damp. You cannot keep moisture out of the fabric of the building, instead you have to let it evaporate naturally by allowing it to breathe. Do that and you don't get damp issues.
My guess at this stage is that the stone repointing has been done in cement. Tbh it's so rare these days that it gets done properly with lime that I can pretty much guarantee it's not. If it is cement, then moisture will struggle to evaporate, being forced now to evaporate from elsewhere which will be the stones (hard for it to do) or through the internal surfaces which is where I suspect the damp patch is coming from given your description - probably from a point slightly lower than the top of the external stonework below the brickwork.
If that's the case then repointing the brickwork isn't going to help. If the pointing is in poor condition then it still needs to be done to protect the mortar between the bricks but it must be done in lime to prevent spalling of the bricks. If the stonework has been repointed in cement then really that needs to be redone properly or the stonework will start to erode rapidly and the damp issues are only going to get worse as moisture levels continue to rise within the wall.
Period properties can't be treated like modern ones, and the use of modern materials on them leads to rapid degredation of the building and problems with damp. You cannot keep moisture out of the fabric of the building, instead you have to let it evaporate naturally by allowing it to breathe. Do that and you don't get damp issues.
jagnet said:
Cement repointing will be much harder than lime. If you try to scratch at it with the end of a screwdriver and compare it to that of the brickwork you'll likely find that there's a big difference in hardness between the two.
<snip>
You may also find old lime mortar to have a much coarser (and wider) grit (range) than is usual with modern builder's sand mixed cement. Not always but it's a sign!<snip>
I used these people in the past http://www.kenwoodplc.co.uk/index.php they do the treatment and re-plastering and provide IIRC a ten year warranty. Wasn't ridiculously expensive given the warranty etc I can't remember how much and we had to have three rooms done.
Matt.. said:
It's an old house without cavity walls. The damp patches on the wall are fairly high up, so it seems like penetrating damp. The wall is mostly stone bricks with a layer of normal brick work between floor levels. The stone has recent pointing, but the brickwork has visible holes. It seems that the water enters here and moves down the wall. Hence looking at sorting the pointing and then fixing the internal rendering/plaster.
Is the plaster on that wall actually blown or just stained from the water?If it's just stained, some decent stain block like Zinsser BIN or Cover stain should sort the stain out, then decorate as normal. Or maybe 2 or 3 coats of a water based stain block like Zinsser 123 +, if you want to avoid oil based and keep the wall breathable. I don't know if Shellac based BIN is any good for breathability?
If the plaster is sound, I wouldn't bother hacking it off to redo it when the problem will sort itself out once the pointing is sorted?
"damp Specialists" are notorious for creating work for themselves.
If the plaster is blown, then just get a normal plasterer in to sort it. The rest of the house doesn't have any problems, and that doesn't have any fancy render or plaster, so once the pointing is sorted, it will be fine, just like the rest of the house?
We had this done in an old terraced house we own which was built in 1885.
The whole downstairs was stripped back to bare brickwork 1.2m from the floor. The walls were drilled and injected. The walls were then sprayed with a waterproof solution before a sand cement was applied. The whole lot was then replastered with a waterproof plaster blended into the walls higher up.
Cost was quoted at £100 a square meter but I got this down to about £85 and used a good local lad with a proven background and inspected his previous work and spoke to previous happy customers.
The manufacturer of the products used came to inspect the work twice before issuing a 20 year certificate. I will dig it out for the name if anyone is interested as I cant remember right now as it was a number of years ago but we never had any further damp problems.
The whole downstairs was stripped back to bare brickwork 1.2m from the floor. The walls were drilled and injected. The walls were then sprayed with a waterproof solution before a sand cement was applied. The whole lot was then replastered with a waterproof plaster blended into the walls higher up.
Cost was quoted at £100 a square meter but I got this down to about £85 and used a good local lad with a proven background and inspected his previous work and spoke to previous happy customers.
The manufacturer of the products used came to inspect the work twice before issuing a 20 year certificate. I will dig it out for the name if anyone is interested as I cant remember right now as it was a number of years ago but we never had any further damp problems.
M3333 said:
We had this done in an old terraced house we own which was built in 1885.
The whole downstairs was stripped back to bare brickwork 1.2m from the floor. The walls were drilled and injected. The walls were then sprayed with a waterproof solution before a sand cement was applied. The whole lot was then replastered with a waterproof plaster blended into the walls higher up.
Cost was quoted at £100 a square meter but I got this down to about £85 and used a good local lad with a proven background and inspected his previous work and spoke to previous happy customers.
The manufacturer of the products used came to inspect the work twice before issuing a 20 year certificate. I will dig it out for the name if anyone is interested as I cant remember right now as it was a number of years ago but we never had any further damp problems.
Yes please The whole downstairs was stripped back to bare brickwork 1.2m from the floor. The walls were drilled and injected. The walls were then sprayed with a waterproof solution before a sand cement was applied. The whole lot was then replastered with a waterproof plaster blended into the walls higher up.
Cost was quoted at £100 a square meter but I got this down to about £85 and used a good local lad with a proven background and inspected his previous work and spoke to previous happy customers.
The manufacturer of the products used came to inspect the work twice before issuing a 20 year certificate. I will dig it out for the name if anyone is interested as I cant remember right now as it was a number of years ago but we never had any further damp problems.
The plaster has blown in one very small area. However, there are patch stains elsewhere on the wall. But it's only one part of a single wall.
One other point is I have some cheaply humidity sensors from Amazon and they show the house to vary between 50 and 70% humidity. 70 seems very high. However, I do wonder if that will reduce once colder weather comes.
One other point is I have some cheaply humidity sensors from Amazon and they show the house to vary between 50 and 70% humidity. 70 seems very high. However, I do wonder if that will reduce once colder weather comes.
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