Damp And Staining On 2nd Floor Around Chimney Breast

[SteveHello1234]

Hello all,

We're soon-to-be Period Property owners and have just joined this forum.... which seems to be most informative and very at-odds with a recent damp company we had round !

My first post on this forum and I'm afraid I must start off by apologising as I suspect I could find the answers somewhere here already. I guess everyone wants reassurance about their own particular situation...

We are hopefully about to buy a Victorian Semi which has been partially renovated (i.e. butchered) and has been empty for some years and I'm afraid its the usual story. Survey reports damp, get damp treatment company in etc etc etc.

One area of concern is that there is lots of staining (and high damp-meter readings) on the chimney breasts and nearby ceilings on the 2nd floor.

1) THE CAUSE
I will be getting the flashings checked asap as this seems the most likely issue. Any opinions on any other likely causes ?

2) THE STAINING
This question is really about the solution to the staining (the room is newly decorated) The damp company said it was probably soot deposits leeching through the walls and is suggesting stripping back top masonry, cement render etc ....

Is that the way to go ? Or just leave it until the wall dries out (assuming the root cause is easily solved ?) and redecorate again ?

3) OTHER DAMP SPOTS IN OUTSIDE WALLS
There are other damp staining issues in the middle of some other outside walls on the 1st floor. Random spots really and no obvious cause and the house has recently repointed (cement before you ask!). Is it likely to be just old moisture coming through from before the pointing was done ?

Cheers all and apologies again for yet another post on damp!

Apparently there is also rising damp as well but thats a whole other issue! Might raise a separate post on that if I don't get shouted at for mentioning the 'D' word yet again

Cheers

Steve :lol:

ps can probably post some piccies if thats useful

 

[MdB]

Hi Steve, welcome to the forum. Don't worry if the following thread goes way off topic shortly. It seems to happen on most threads (and I'm as guilty as the rest...)

As per the damp, has the building been shut up tight most of the time during the last couple of years it has been empty? If so, some of the problems may be due to poor ventilation allowing moisture build up and condensation to form. This would be my guess as to your outside wall issues.

Pictures would be useful and so would details of what sort of damp treatment has been applied.

Can't really comment on your chimney (I'm new to all of this) but when others talk about cow sh*t, they are being serious....

 

[northern monkey]

You'll probably get loads of replies to this, but I'll throw my hat in the ring anyway.
Just had a similar problem with damp showing through where the upstairs chimney breast meets the ceiling. The house is 140 years old stone built cottage which I had just had re-roofed in stone. The roof needed doing anyway but I told the roofer to pay particular attention to the chimney flashings (I thought this was the culprit). While replacing the roof, we found the chimney had been sealed on one side (we found that there were to chimneys exiting through 1 shared chimney stack). The pot which I thought was allowing ventilation through the chimney was sitting on the end of a flue liner.
When we removed the stone from the top of the chimney, we found the chimney was wet with condensation. We have since vented the chimney and fitted 2 additional pots to the top of the stack (although the gas fire still has its own flue liner and seperate pot). The chimney breast is now drying nicely.
As for the other damp issues - I will be the first to say please do not rely on 'expert' damp companies who will diagnose rising damp and suggest inappropriate damp treatments. Pay to have a survey done by an independant timber and damp surveyor with nothing to sell. My last survey cost £150 but saved me, and the building, so much more.

 

[SteveHello1234]

Re being sealed up.... The downstairs has all the windows nailed shut. The 2nd floor has all the windows stuck open (due to very poor painting of the sash windows) - told you it had been bodged !

 

[Nemesis]

Don't worry if the following thread goes way off topic shortly. It seems to happen on most threads

Well, life would be dull if we stuck to the point always!

Like living in a Barret Box. :shock:

The main issue at the moment I would suggest is a mortgage one - if the mortgage company sees the reports, it's possible it will have a fit of the conniptions and demand inappropriate treatments as suggested by the supposed 'experts' and retain some cash.

If not, it seems to me you are on the right track with your ideas, and in the longer term, as suggested, a spot of cash spent on a genuine expert with period buildings expertise can save a whole shedload.

Do the minimum to make the place habitable and go a step at a time, as gently as possible.

Yes cow sh*it works, but maybe seeing what is causing the damp is the first step.

 

[SteveHello1234]

Thanks for the replys folks - its a very responsive forum which is great !

The mortgage company have imposed no restrictions and have not retained any of the loan which sounds unusual after browsing this forum a little

re. the staining (which is quite bad). Whats the best way to deal with this - assuming the walls have dried after we've moved in ? If we redecorate - will it just come through the new paint ?

 

[Cloudscape]

Your house sounds very much like my Victorian semi. If it's as bodged as you say, I'm assuming the walls are all skimmed (if not completely plastered) with gypsum plaster.

I had all the signs of 'damp' that you describe, brought about by chimneys that were wide open (crumbling) at the top and sealed at the bottom, leaky or non-existent gutters, areas of exterior pointing that were missing - all the usual culprits.

If you're happy your chimneys are as renovated as they can be, and the roof, flashings, gutters and pointing are OK... first of all you need to get the interior as dried out as you can (could take a while).

If you do have gypsum plaster on your walls (like mine) some of the dark staining isn't coming from inside chimneys or through the wall. When gypsum plaster has been made damp for a prolonged period of time, it starts to turn brown and changes its chemical composition. It becomes hygroscopic and will actively suck in moisture, even from the surrounding air.

I needed to do a quick cosmetic fix on a couple of rooms and just lined the walls with very thick lining paper (left unpainted). Within a few months, small dark areas started appearing on the paper. They felt permanently slightly damp, even 8 years later, when you would have thought the house would have dried out.

The problem was worst in the kitchen (steam) and in bedrooms (all that water you breathe out during the night). In the course of some partial replastering, and relining, most of the darkened plaster was removed. In some cases, on the surface of the paper, you could clearly see which was old plaster, and which was new by light and dark areas.

Incidentally, I began to think that in some places, there never had been damp penetration. The problems in the plaster had been set up by poor ventilation over years and years, and condensation on the coldest parts of the walls (a chimney breast will be cold if the chimney is never used?).

So selective replastering is one intermediate fix. Chop away all the darker plaster.

Since the walls are gypsum plastered, and the house is architecturally beyond redemption, I used a damp-proof paint here and there, where any small stubborn patches of plaster were still causing problems. This wasn't to stop damp coming through the wall - it's the opposite - to stop the plaster being able to suck moisture from the room.

Once decorated, the walls now look fine.

 

[Matt Green]

Chimney breasts are tricky to diagnose without photos, there are a number of different causes. As per the damp thread, the more information you give us, the better the diagnosis:

What are the symptoms- what are you seeing? By staining do you mean salt deposits, discolouring, condensation?

What is the wall covered with?

It there a pattern to the damp stains? Mostly at the top, following the flue line?

Photos: photos help a lot. :wink:


Matt

 

[SteveHello1234]

thanks matt - will get some piccies at the weekend

 

[SteveHello1234]

Thanks for all the replies - piccie is here. I've had a look at the flashings from the ground and they look new so maybe this is just 'old' damp coming through ? Or am i just being hopeful ?

On another note - the fireplace has been butchered and covered with white paint (gloss i think) - any tips on how to remove (sandblasting in situ has been mentioned!)

 

[Moo]

Nitromors or one of the poultice systems is much less messy and damaging, and much more satisfying than sand-blasting.

 

[Matt Green]

Thanks for all the replies - piccie is here. I've had a look at the flashings from the ground and they look new so maybe this is just 'old' damp coming through ? Or am i just being hopeful ?

No, not at all. That looks about right for slow drying. The water looks like it's come in from above and it now moving from the fabric into the room.

Depends on the history of that area now: was there a leak that's now been fixed, has the plaster been changed, is the wall emulsioned? It doesn't lok so bad and will dry out eventually as long as the flashing is sound.


Matt.

 

[Penners]

On another note - the fireplace has been butchered and covered with white paint (gloss i think) - any tips on how to remove (sandblasting in situ has been mentioned!)

Sandblasting iron is less destructive than sandblasting timber. But unless the operator is thoroughly experienced, you could still end up with some loss of fine detail.

Stripping is a much better idea.

Strippers of Sudbury make a variety of good stripping poultice products. Have a look at the entry on cast iron on this page of their website.

 

[SteveHello1234]

Thanks guys - I should say we haven't quite bought the house, just acting on reports from the surveyor and a subsequent damp treatment company.

re. the damp patch - yeah in theory the house was reroofed and reflashed about a year ago, (wall emulsioned) but has been empty and unheated since so hopefully it is just drying out

re. the fires - thanks for the tips. Will use a paint-stripper at some point in the future (have many more important jobs to do before then!)

Cheers

Steve