Weird Moisture Patch by chimneybreast

[Nige F]

he just looks for trouble 765 ..I mean 24/7.

yes, tel765 was one of his incarnations then there was a ted or 2

 

[Deleted member 292770]

yes, tel765 was one of his incarnations then there was a ted or 2

and given the ‘word searches’ could have been a bob too.

 

[Nige F]

and given the ‘word searches’ could have been a bob too.

bob or nob?

 

[KM27]

No worry about all and any questions.

The remedial measures I'm describing below are a worse case scenario. But no specialist Damp man is needed. Even a Handyman could do the inside work.

However many flues go into the chimney stack on the roof - each & everyone needs to be vented top and bottom.
Each room with a chimney breast running through it will typically have a fireplace - many fireplaces have been blocked off over the years thereby removing the bottom venting so to speak.

Assuming that your first floor flat fireplace is blocked off and the fireplace in the room below is also blocked off - then both "blocking offs" will need opening up to allow sweeping.
And then say a 9" x 3" or a 10" x 6" hit and miss vent is inserted into where the open fireplace used to be when the openings are re-covered.
Where the flues finish at the top of the stack, the flues (all flues) will need an appropriate terminal.

Its a pretty simple DIY job to insert a hit & miss vent in the room c/breast.
Opening & closing the blocked fireplaces is DIY doable
But all flues that run up the c/breast in your room will need sweeping and venting.

Modern roofers are nowadays providing the householder with before, during & after pics/vids of any roof work.
All roofing work should be done by professionals.

The stained decorated surfaces need hacking off back to bare brick, and rendering with a sand & lime mix render.
It could be that much more of the c/breast surface is contaminated - but a plasterer could easily deal with it.

The above remedies are a possibility but you could of course always try what was suggested by jj4091?

Thanks! This is all very useful.

Is this not a vent (external)? It is to the left of the chimney stack as you can see (when viewed from inside the room)..

https://ibb.co/h9v4J3D

Either way, looks like I need to find a builder and a plasterer.

 

[KM27]

Your new pic. looks to me as though condensation is just running down the surface of the wall & damaging the decor. I am just guessing but it looks like he room is a kitchen & your problem is excess steam condensing on cold chimney breast when cooking. If so you need more ventilation in the room in general when cooking. Do you have a cooker hood or extractor fan? If not the you may just need to open a window when cooking.

So possibly we have two problems due to the way the chimney breast has been dealt with... condensation due to temp differential and then lack of venting...

I have a humidity meter and dehumidifier which put on when cooking, washing up, drying washing. But was worried that it would be sucking the moisture in the chimney back through the plaster if left on for too long?

 

[jj4091]

Thanks! This is all very useful.

Is this not a vent (external)? It is to the left of the chimney stack as you can see (when viewed from inside the room)..

https://ibb.co/h9v4J3D

Either way, looks like I need to find a builder and a plasterer.

I think that is an old boiler flue rather than a vent

 

[KM27]

I think that is an old boiler flue rather than a vent

Thankyou! I will try to fit a hit and miss vent and see if that makes a difference.

 

[KM27]

No worry about all and any questions.

The remedial measures I'm describing below are a worse case scenario. But no specialist Damp man is needed. Even a Handyman could do the inside work.

However many flues go into the chimney stack on the roof - each & everyone needs to be vented top and bottom.
Each room with a chimney breast running through it will typically have a fireplace - many fireplaces have been blocked off over the years thereby removing the bottom venting so to speak.

Assuming that your first floor flat fireplace is blocked off and the fireplace in the room below is also blocked off - then both "blocking offs" will need opening up to allow sweeping.
And then say a 9" x 3" or a 10" x 6" hit and miss vent is inserted into where the open fireplace used to be when the openings are re-covered.
Where the flues finish at the top of the stack, the flues (all flues) will need an appropriate terminal.

Its a pretty simple DIY job to insert a hit & miss vent in the room c/breast.
Opening & closing the blocked fireplaces is DIY doable
But all flues that run up the c/breast in your room will need sweeping and venting.

Modern roofers are nowadays providing the householder with before, during & after pics/vids of any roof work.
All roofing work should be done by professionals.

The stained decorated surfaces need hacking off back to bare brick, and rendering with a sand & lime mix render.
It could be that much more of the c/breast surface is contaminated - but a plasterer could easily deal with it.

The above remedies are a possibility but you could of course always try what was suggested by jj4091?

Thanks again - three clarifications please:

1. To fit a hit and miss vent can I just drill into the plasterboard (cavity), clear hole and fit over top? or is it a little more complicated?
2. My understanding of flue is it is where the smoke etc goes from a single fireplace? One flue per fireplace? In my situ - the flat below will have one flue and we will have one from ours? Is this correct?
3. Sweeping - this suggests all the plaster covering the old fireplace needs to be opened up and done before replaster and fit vent... is this correct?

Thanks!

 

[KM27]

Hello. I finally got round to putting a vent into the plasterboard as per the suggestion. There was a brick wall immediately behind the plasterboard - for some reason i was expecting it to be an empty like a fireplace? Does this mean they have bricked it up? and if so - do I need to take a brick out to vent that as well?

 

[Harry Bloomfield]

do I need to take a brick out to vent that as well?

Yes! If the idea is to dry a space out and it to remain dry, then there needs to be a flow of air, in at the bottom, out the top via a cowl.

 

[opps]

Hello

Moved in to new property 6 months ago. Weird moisture patches, and condensation drops appearing on one wall where chimney breast is.

Chimney needed some work - new flashing box and re-pointing. This stopped a leak that we could hear when it was raining.

However - still getting these weird moisture patches on the ceiling (Attic above), and condensation drops appearing along the wall where chimney breast is.

Bought dehumidifier which has reduced humidity but not sure has impacted moisture along that wall.

Pictures:

https://ibb.co/LvK2nct - Moisture Patch, like a ring
https://ibb.co/HCB5MkR - Yellow discolouring, moisture patch is adjacent to this
https://ibb.co/D4gCwjK - another angle showing discolouring

If I am ruling out weather related (i.e. roof) - what does this leave? Heating pipes go under the floor... (boiler is in this room and only one radiator to the left of photos, no radiators in attic!)..

There is a water tank in the attic but not sure it is being used as we have a COMBI boiler....

Any thoughts, ideas welcome as this is really puzzling me.

I have experienced the same in a customers' home. When redecorating the room I used SBR over the water stains on the chimney breast.

The water stains reappeared in the winter. The customer had already paid £20K to have his semi- detached re-pointed. The pointer gave him a number to phone. The new fellow explained that soot lined chimneys will hold moisture and release that moisture (through the chimney breast during the winter).

The advice was to hack away the plaster and use sand and cement.