10 months of DAMP problems. See Photos. Please help!

[Dampadoodle]

Hi all,

Ok. We are at our wits' end. the following is our damp story and any help would be appreciated....

The property is a ground floor flat in a terraced road (1890?). We have had a 'damp' problem since purchasing the flat in Oct 2005, where we initially noticed a stain showing through the cavity wall between the kitchen and the bathroom (on the bathroom side). The bathroom has a concrete floor, kitchen is suspended (approx2ft - wooden floorboards)

We then looked behind the ground level units in the kitchen (against the party wall) and behind the fridge and saw extensive evidence of damp (staining and strong damp smell). After investigating the bathroom plumbing, we fixed a leak that was putting about 1/4 pint water under the bath every time the shower was used (and this water followed pipes down into the area under the kitchen floor). We also ensured that the airbricks for the whole property were cleaned and blockage free.

We hoped that this had solved the issue but the smell didn't seem to disappear and the staining continued as well. We are now needing to install a new kitchen and want to ensure that when we replaster the walls and install the units, there will be no more damp problems.

We've had quotes from damp companies (wielding damp meters) and also had people on the roof to check the state of the chimneys, with quotes for repointing work and re-flaunching the chimney.

A few weeks ago I took off some of the low level plaster next to the floorboards and it was quite 'mushy' but now its exposed it seems to have dried out a bit. So we are now unsure if we have other ingress of water from somewhere (mains? drains? chimney? water table?) or if the old water from the leak is still slowly drying out.

The property has an old slate course under the kitchen, concreted side return, and small decked garden area. The damp is not on the external walls. There is evidence of damp in our neighbours flat on the other side of the party wall (peeling paint) and in their bathroom. There is no damp in the flats above.

So a few questions

1) How long would it take for the moisture from the bonding to dry out? If at all?

2) Could the damp be caused by bad pointing/flaunching on the chimney stack? (we think that the 'damp' wall smells more after it rains and the stack is directly above the party wall)

3) If the damp is caused by a dodgy chimney stack, wouldn't the flat above be experiencing damp too? - I ask this because we had a roofer come round to give a quote for the stack and he reckons that its fine in its present state and needs no more work doing to it, and that it is not causing the damp or upstairs would have issues too.

4) What should we replaster the walls with? Should we use lime? or sand/cement/waterproofer as everyone who comes round seems to suggest? or dry-lining (plasterboard). As floor level units are going to be in front of the areas where damp can be seen, we dont really mind the look of it, just mind drying time (kitchen is arriving in a week to be fitted by a friend). We have solid wood worktop and really dont want to ruin this by putting it near drying plaster/render whatever(!) too early.


This is the damp (or drying stains from previous damp) behind the units against the internal party wall.

The following is the view under the previous photo (taken under the floorboards). The damp in the photo above is slightly to the left, above the brick 'pier' (the thing that looks like a wall on the left of this shot is actually a brick structure sticking directly out from the party wall - could this have been an old hearth?)

This is a shot of the corner of the brick pier. So the camera is in the same location as before just rotated about 20 degrees to the left.

Next is a shot looking past the brick pier, parallel to the party wall. So,the camera is in the same location as before, just rotated to the left by about 10 degrees.

Last two shots above ground again! beginning to hack off the old bonding.

In the last photo, I'm pointing to some black, very wet material, a bit like wet charcoal.

Okay. So. any ideas? any answers to the questions above?
If you need further info tobe able to helpthen let me know!!

Thanks in advance for your time and help.

Pete

 

[Dampadoodle]

I've now uncovered some more of the old bonding and this photo shows that there seems to be some odd brickwork. On the left of the shot the brickwork is all normal and in straight lines and then it gets all messy on the right, with bricks shoved in and mortared any old how.

Could this be where an old (v small) fireplace was? As mentioned before, there is a chimney directly above this wall, but no chimney breast on this side or the or in the other flat the other side of the wall. It only still exists in the flats above.

There's been more of the black stuff too. It smells and feels just like soil!

Does this shed any further light? Should I try to remove a brick or two so that I can put in a vent?

 

[mark_j_k]

We used to have soil appearing through our cellar walls when it rained at one point, it was very wet too. Turned out to be a cracked soil pipe, pipe repaired and no more problems.

 

[Johneds]

It's going to be difficult to tell for sure what is going on without hacking most of that plaster off and possibly removing a bit of masonry behind. So you might as well get on and do it. In any case. it looks like Carlite browning (or bonding) to me which is a disaster in damp situations.

The dampness could easily be residual from the leak under the bath. Depending how wet it got it would take quite a while for that to dry out - think in months as a minimum. Especially with the Carlite plaster which will tend to trap moisture.

If there is an old flue behind that could well be leaking from above. Again you will need to get at it to check for sure and to dry it out.

 

[Moo]

Just thought about your new kitchen -

Why bother to plaster the walls behind the new units? You've said that once you'd exposed a patch of bricks they seemed to dry out, so if you left all of them exposed where they won't show, there'd be nothing to hold the damp in. And you'd have saved yourself a bob or two as well.

 

[Dampadoodle]

Thanks for your ideas - really appreciate it.

We had thought about leaving the bricks uncovered - and this may well be the best in terms of letting the wall breathe - but just knowing that that ugly mess was behind there - eeeguh. Having said that, what about putting lime plaster (or something else that is breathable?) behind there?

Is there an issue with putting such a breathable material behind kitchen units? would it mean that it was always moist behind them and cause a bad smell? would it have an effect on the nice solid oak worktop we're going to install, like warping it?

 

[Schoolmarm]

Erm, two things. Was a fridge against that damp wall?


If you are looking at the back wall of a removed chimney breast, the people upstairs are looking at the front wall of the chimney breast. Therefore they will not see the chimney leaks upstairs if that makes sense.

 

[Dampadoodle]

No, just kitchen units with no appliances.

If the brickwork we have uncovered was originally the 'back' of the chimney then this would mean the wall from this point up to the ceiling would also be showing signs of damp perhaps but there's no sign at all.

 

[NT]

I dont see much point plastering a wall that wont be seen. Clean it and limewash would end the mess, lime is breathable and has biocidal properties. It also bonds loose dust.

NT

 

[Lime]

The bricks behind the plaster/carlite browning/bonding appear to have been painted with a lime wash originally. The thick plaster covering is not helping the situation at all.
You refer to this wall as a cavity wall. Does it have a cavity or is it solid?

My first impression is that this is typical of many patch and mend repairs that over the years has neither solved the damp problem nor improved the situation in the long term.
The jumbled brickwork may be hiding all sorts of things. It could be where an old "copper" once stood and is just a patched hole, it could be a flue or perhaps where pipes once ran through the wall.

If the water in the brick is only coming in from the bathroom leak and if the all leaks have been stopped I would expect the damp to be improving.
If there is suspicion that water is coming in anywhere else, such as via the chimney, that needs to be stopped too.

Is the bathroom an addition added albeit a long time ago to an outside wall?
If it isn't, do you know if the solid bathroom floor is original? What was the room used for before it was a bathroom?

My suspicion is that the solid bathroom floor on the otherside is contributing damp to the wall in some way, probably due to it's construction or some subsequent damage such as a screed.


If it was my property and I was able to empty the kitchen ( :shock: ) I would take up several floorboards next to the wall (has any woodwork under the floor been renewed?) to inspect and clean/clear the slate of the dampproof course and ensure that all timbers are sound. I would also clean out the rubble and rubbish on the soil below while I was there too.

Leaving the brickwork free of plaster is a good idea for the moment.
It will allow the wall to dry more but it must have some ventilation.
If you are going to have a solid oak worktop running tight up against the wall you need to allow some ventilation space behind the kitchen units and openings at either end to allow the air to circulate otherwise the moisture will not escape.

Having more plaster or waterproof cement plastered on the wall is not just a waste of time it will create further damp problems IMO.

 

[Dampadoodle]

Okay,we've taken some more of the horrible, claggy bonding off now. It seems that the bonding has been put on as a 'remedy' for previous damp. There are even a couple of drilled holes in the brickwork about an inch from the floorboards that look like sample holes possibly.

This photo shows the original uncovering work to the left (party wall) and the new work all along the wall that backs on to the bathroom - this had bonding from the floor to about 6 inches up where it changes to a really solid material like cement with a skim of pinky plaster over it. Could this be damp coming through from a concrete (or solid of some kind) bathroom floor? There are injection holes on the external bathroom wall.

The following photo shows the fluffy salts (?) on the far left of the previous photo

This next photo shows the solid cement surface onthe right edge of the excavations and the pinky bonding at the top edge

This last one is a side view of a chunk of the bonding that came off - does this confirm it as being Carlite browning? (it's actually more pink in colour than this photo shows)

 

[Dampadoodle]

Lime - thank you for such an in depth view. Great to hear from someone with an opinion but without something to sell.

I dont think the party wall can be a cavity wall - there's just not enough space.

I'm not sure about the bathroom's history - the only thing I know for sure is that the floor is solid and has been injected. The left half of the wall between the kitchen and the bathroom is brickwork and the rest is a stud wall - the upright timber closest to the brickwork (at the right hand edge of the long, thin low level excavation in the photo in the previous post) is completely spongey.

 

[Lime]

This is much more serious if timber is rotting.
You must get more air circulating under the floor perhaps by inserting or enlarging the ventilators in the wall. The timber problem will not go away and now is the time to sort it out.
One of the problems in houses with mixed flooring such as this is that underfloor air circulation is stopped or impeded by the solid floor area. Extra ventilators will help.
Also the air circulation will be improved if you remove a few bricks from the underfloor dwarf walls. Obviously you need to be careful not to remove the "wrong" brick or too many but the walls appear to to be restricting air flow quite badly.

 

[Dampadoodle]

The wall between the kitchen and bathroom has definitely been injected directly into the brickwork (not mortar) at some point-there is a line of holes that appear in each brick along the level uncovered (they are not sample holes as first thought).

The timber that is spongey is just the upright for the plasterboard and also a random horizontal about 6 inches long that is placed in the wall like a brick, butting against the upright.

 

[Lime]

Right, The wall between the kitchen and bathroom has definitely been injected directly into the brickwork (not mortar) at some point. There is a line of holes that appear in each brick along the level uncovered.

I think this is a good example to show that the recommendations made to you to inject and replaster don't work!

 

[Lime]

The timber that is spongey is just the upright for the plasterboard and also a random horizontal about 6 inches long that is placed in the wall like a brick, butting against the upright.

I misunderstood you as I thought you referred to the floor...that's good!

I would still attempt to increase the air circulation under the floor though.

 

[Dampadoodle]

Absolutely right - I'm looking forward to showing the holes to the guy coming tomorrow night to give an estimate for replastering or rendering with sand/cement/Sika waterproofer (he previously mentioned that he had a mate who could inject for us and that it would be sensible!).

There is one airbrick (each recently cleared) for each room of the house (apart from the bathroom which has a high level extractor). Are you saying there should be more?

 

[NT]

quote="Dampadoodle"

> Absolutely right - I'm looking forward to showing the holes to the guy coming tomorrow night to give an estimate for replastering or rendering with sand/cement/Sika waterproofer (he previously mentioned that he had a mate who could inject for us and that it would be sensible!).

so why have him round?


> There is one airbrick (each recently cleared) for each room of the house (apart from the bathroom which has a high level extractor). Are you saying there should be more?

If youre referring to underfloor vents, more would lower the RH and reduce dampness.


NT

 

[Dampadoodle]

Hi NT.

Getting him round anyway because we need skimming work on the non damp parts of the wall - also interesting to hear every opinion.

RH = relative humidity?

 

[Dampadoodle]

The kitchen/bathroom wall in full. The timber I was talking about earlier is roughly in the middle of the painted section, at the end of the exposed brickwork directly below the copper pipes. It just so happens that exactly behind that section lurks the shower end of the bath that was leaking when we moved in. From that point onwards to the right is stud wall.

Zoom in on the area described above (you can see the small piece of horizontal timber, the vertical piece of studwork next to it and also 3 of the injection holes):

So would you think that the professionals we need are:

1 -Builder to install additional airbricks and replace the rotten studwork and plasterboard
2 -Lime plasterer to replaster at least the area in the picture above (as this will probably be visible - it will be behind the sink cupboard) and to limewash the rest - anyone know a good one in SW London?
3 -Plasterer to skim the other parts of the wall (lime plasterer could probably do this?)
4 -Anyone else? someone to give advice/help? Does anyone know a reputable expert in SW London? Would he/she be a 'building conservation' surveyor or someone else? We really want to be confident that when we install the kitchen, all will be sorted - a tough ask obviously.