Flue causing damp patch?

[PaulJFT96]

Hi,

Not sure if the right forum or not but here goes...

We have noticed a darkened area on one of our interior bedroom walls over the last few weeks. Pics below.

I got in to the loft this morning and none of the floorboards seemed wet and certainly no damp up there was visible. However I noticed the Flue/Chimney runs down pretty close to where the mark is.

Is it possible some sort of damage or damp to the flue could have caused this?

Or could there be alternative causes?

Thanks in advance.

 

[^woody^]

Yes if the flue is in that location, then it's either flue condensation from an unventilated/unused flue, or water penetration from an uncapped/ unused flue.

 

[PaulJFT96]

Cheers Woody - What would you suggest moving forward? Is it a job for a roofer or could I possibly look in to a fix myself?

DIY novice by the way.

 

[^woody^]

You need to read a few threads about disused flues.

If you're not using the flue, and especially if it's blocked off top or bottom, then it needs ventilating. Otherwise it may need attention to the chimney pot or the chimney flaunching - the mortar around the pot.

There is potential for it to be a flashing problem between the stack and the roof tiles. But normally if this was the case, you would expect to see damp on the surface of the stack in the loft and not just as a patch halfway down the bedroom wall.

If that stain does not go away once the (flue) problem is rectified, then you will need to hack off the plaster and brush on a sealer to the wall. Otherwise it will just dry out naturally.

 

[Blagard]

I totally agree with what Woody says if it is on a flue construction, but if it is only nearby then I would suspect something else. Check to see if anyone previously buried some pipework there, I would expect it to be visible in the loft. Other possibles are tank overflows saturating the wall outside and water finding a route through. Even a leaking gutter could cause it if the water can get back to the wall (not likely with a decent eaves overhang)

 

[PaulJFT96]

I totally agree with what Woody says if it is on a flue construction, but if it is only nearby then I would suspect something else. Check to see if anyone previously buried some pipework there, I would expect it to be visible in the loft. Other possibles are tank overflows saturating the wall outside and water finding a route through. Even a leaking gutter could cause it if the water can get back to the wall (not likely with a decent eaves overhang)

Cheers mate and thanks for the other suggestions. I'll get up in the loft tonight and see if I can see evidence of pipework etc. If not I'll check the gutters too.