Damp patch in loft room

cloud21

Have this leak in my loft room that only appears when it pours. Roofer has recently repointed the chimney stack. Since then the leak has eased off but I can still feel the ceiling getting damp when it rains, starting where I’m pointing.

Been recommended that the ridge tiles need doing, I’m worried that this won’t fix it though considering where the leak starts.

Roofer has had a through look and thinks flashing and tiles in the leaking area are all ok.

Any advice?

stuart45

If the pointing helped reduce the moisture it suggests that it's penetrating the stack masonry. Nowadays, chimneys have at least one lead tray in the stack to prevent this happening. Years ago they weren't so necessary because the open fires usually dried out any water getting though, and loft rooms weren't so common and any damp wasn't spotted up there. Once it's a living space and decorated any damp shows up.
The flashing looks OK, but you can't see the soakers conditoon.

Eldi_Dos

@cloud21
Could you describe or post photo of what type of pot, if any,is at the top of the stack.

Swipe

Ask the roofer to try some Stormdry masonry paste on the chimney stack and top flauching around the pots. It fixed my chimney issue.

cloud21

Eldi_Dos said:

@cloud21
Could you describe or post photo of what type of pot, if any,is at the top of the stack.

Sorry for late reply. Roofer says it’s condition is fine.

Eldi_Dos

Assuming there are only two fireplaces using the chimney?
The pots in the photo look to me that they would stop water ingress and keep chimney ventilated.

The stone slabs used as corbel's, there seems to be a gap between two of them, that would be my prime area to check, and are they sitting so that water runs away from chimney.

Edit; not 100% sure corbel is correct description for those stone slabs.

stuart45

Eldi_Dos said:

Edit; not 100% sure corbel is correct description for those stone slabs.

I'd call it an ovesailing course rather than a corbel. They are similar, but a corbel is a method of taking some loads out from the wall in a cantilever way, whereas an ovesailing course is usually to protect the brickwork below from rain. You often get oversailing tile courses under the brick on edge top to a garden wall.

cloud21

Eldi_Dos said:

Assuming there are only two fireplaces using the chimney?
The pots in the photo look to me that they would stop water ingress and keep chimney ventilated.

The stone slabs used as corbel's, there seems to be a gap between two of them, that would be my prime area to check, and are they sitting so that water runs away from chimney.

Edit; not 100% sure corbel is correct description for those stone slabs.

Yes, and interesting point, never noticed that. Roofer still believes it’s the ridge tiles so will get him to fill those gaps when he does them maybe. As mentioned it only gets damp occasionally, so possibly the wind is helping to blow rain directly down that gap more, but it still shouldn’t leak through.

I’m still wondering if something is wrong with this tile as that is where the leak starts but roofer has checked it and says it’s fine.

Eldi_Dos

cloud21 said:

Eldi_Dos said:

Assuming there are only two fireplaces using the chimney?
The pots in the photo look to me that they would stop water ingress and keep chimney ventilated.

The stone slabs used as corbel's, there seems to be a gap between two of them, that would be my prime area to check, and are they sitting so that water runs away from chimney.

Edit; not 100% sure corbel is correct description for those stone slabs.

Yes, and interesting point, never noticed that. Roofer still believes it’s the ridge tiles so will get him to fill those gaps when he does them maybe. As mentioned it only gets damp occasionally, so possibly the wind is helping to blow rain directly down that gap more, but it still shouldn’t leak through.

I’m still wondering if something is wrong with this tile as that is where the leak starts but roofer has checked it and says it’s fine.

Just a laymans observation but the flashing just north of the area you have circled looks short to me, I could see wind driving water along those tiles under the flashing. Where is that area in relation to the damp patches ?

stuart45

It should have soakers under the slates, so the cover flashing only stops the rain getting behind the soakers from the stack. It can be even a bit shorter than that. 

Eldi_Dos

stuart45 said:

It should have soakers under the slates, so the cover flashing only stops the rain getting behind the soakers from the stack. It can be even a bit shorter than that. 

So would it be feasible that at some stage flashing has been renewed and older soakers left in place and are begining to fail now?