Roof Leak - Help, Panic!

[MarkFish]

I've got a damp patch in a ceiling just below the corner of a chimney.

4 pics of the outside here:
http://i40.tinypic.com/35je4pv.jpg
http://i40.tinypic.com/fa8nxs.jpg
http://i39.tinypic.com/p6d5j.jpg
http://i42.tinypic.com/2hd2ut5.jpg

I've never had the slightest success chasing leaks so would welcome the forum's expertise.

I can just about get to half the chimney in the loft and the bits I can touch feel dry but that means little I guess.

Where's it coming in? Flashing? Pointing?

If I need to have both done to be sure, what's the cost likely to be?

Where actually having the adjacent flat roof replaced this week - are they likely to have the skills to re-flsh the chimney?

The chimney will never be used again - what's a rough cost of removing the chimney above roof level. (I assume they'll be able to match the tiles?)

Could the chiney be a total red herring?

HELP!

...and TIA.

 

[ladylola]

To be honest the flashing doesn't look in too bad a condition, ok so it wouldn't hurt being repointed or the pointing replaced with leadmate sealant.
A common problem in these cases is the back gutter which we can't see in the photos and would require inspection by climbing on the roof.
I can see quite a bit of moss on the top of the chimney and it's also possible the flaunching has failed and water is penetrating there. Also is there some sort of cowl fitted to stop rainwater simply comming down the inside of the chimney.
Akward to give a price to remove the stack, it'd depend on access etc but should take no more than a couple of days to remove and make good.

 

[MarkFish]

Thanks for the response LL.

To be honest the flashing doesn't look in too bad a condition, ok so it wouldn't hurt being repointed or the pointing replaced with leadmate sealant.
A common problem in these cases is the back gutter which we can't see in the photos and would require inspection by climbing on the roof.

I knew I was going to have to look at that. I'd kidded myself that because the visible damp is the visible side of th ecimney the water must be coming in there, not the back section. Deep down I knew I'd have to look.

I can see quite a bit of moss on the top of the chimney and it's also possible the flaunching has failed and water is penetrating there. Also is there some sort of cowl fitted to stop rainwater simply comming down the inside of the chimney.

There is a cowl which looks good at a distance, but the condition of the flaunching is anyones guess. There is some kind of damp course three 'visible' bricks up. I wondered if this might mean that ingress from higher up was less likely but I guess it can't be ruled out.

Akward to give a price to remove the stack, it'd depend on access etc but should take no more than a couple of days to remove and make good.

It's really tempting to get rid of the chimney.

I'm having a new flat roof put on this week. I'm tempted to ask them to repoint while they do that and see what happens. On the other hand any chimney work we have done will involve using the flat roof as a work platform so I'm tempted to put that work off until this leak is solved so save wear on the new flat roof. (Otherwise I can see the new roof being destroyed.) Mind you, I guess I can insist on the using scaffolding.

Thanks again.

 

[xr4x4]

Second to last picture.

Looks like dark staining on the wall under the guttering below the Chimmney.

Also the guttering looks like it's bowing too in the same spot.

 

[cotswoldbuilders]

If your never going to use the chimney again, take it all down and tile over.
All the pointings shot on it.

 

[xr4x4]

If your never going to use the chimney again, take it all down and tile over.

That's a bit extreme, do you recommend everyone should do that when they are not going to use their chimney?

 

[ladylola]

Second to last picture.

Looks like dark staining on the wall under the guttering below the Chimmney.

Also the guttering looks like it's bowing too in the same spot.

yes I looked at that "bowing" too but I wasn't sure whether it was a photographic distortion as the brick courses looked a bit "bowed " too

 

[cotswoldbuilders]

xr4x4 no I dont reccomend every one take there stack down, the op suggested it, and said they are never using it.
The pointing is crap, by the time you have cut it all out and repointed it the stack could have been taken down, tiled over, job done.
How can you tell the leak is caused by the gutter from a photo, it could be any where, can you see behind the stack.
The only sure way of knowing what the problem is, get on the roof.

 

[xr4x4]

I take your point.

I wasn't saying the leak was coming from the gutters, I was just pointing out something that maybe someone hadn't noticed.

 

[catlad]

Cheaper to drop it than point it.

 

[MarkFish]

Second to last picture.

Looks like dark staining on the wall under the guttering below the Chimmney.

Also the guttering looks like it's bowing too in the same spot.

Good spot, and thanks for your comment.

The effect you're seeing is distortion, however, I wouldn't be surprised to find that the gutter was leaking but the damp inside the house is a good foot higher than the guttering. So I *think* that can be ruled out. (I'm sure water can soak it's way up the plaster but I don't think that's happening in this case).

Mind you I've no reason to suspect the chinmey other than the location of the damp patch. It could be coming in anywhere.

 

[MarkFish]

More information.

It hasn't rained but the damp patch appears worse today. I suppose the 'extra' dampness *could* be condensation from inside. There's two of us and a baby breathing in an out in there and I guess the water would typically condense on the colder damper bit. Perhaps it's worse 'cos of that.

There are no pipes and no souce of water anywhere near the ceiling at this point. There are water pipes under the floorboards - surely I can rule out water climbing from the floor to the ceiling?

I've got access to the top of the damp area and I can see the top of the plasterboard is bone dry. So at that point the damp must be coming from the side or below. Everything I can reach in the loft around the chimney is bone dry.

We had a window fitted in that room this week. I'm now starting to wonder if that disturbed something. I'd totally ruled it out before because the window is a good foot below the damp and 3 feet to the side and I couldn't imagine water moving diagonall up. However, now I can be pretty sure the damp isn't coming from directly above the room [1] I guess it's possible.

A builder mate is going to have a look and I think we'll ask the guy who fitted the windows for his opinion, but I think I'm basically on my own here.

Anyone have any thoughts?

[1] Unless it's coming down inside the chimney brickwork which still seems likely to me.

 

[BethesdaSlate]

The lead flashing to the sides of the chimney is poorly detailed and could allow water to run in under the sides - there should be individual lead soakers for this type of tile (I think they are Redland Stonewolds) It may have been leaking at this point for years but has only shown recently as the felt may have finally deteriorated. The felt failing may also explain condensation getting through; as it can form on the underside of the tiles drips down onto the felt and would normally run out at the eave.

The chimney itself looks Ok, it even has a lead DPC running through just above roof level which is good.

I would strip the tiles around the chimney- replace the lead, properly, and maybe stick a vent tile in close-by to help vent out existing damp.

 

[xr4x4]

Got any pictures of the inside?

So we can get an idea of the room layout, in relation to the chimney.

 

[MarkFish]

Thanks BethesdaSlate, a very useful post. Not least because I think you've identified my tiles - that could be useful in future, and probably in the immdeate future.

The chimney itself looks Ok, it even has a lead DPC running through just above roof level which is good.

Does the DPC mean it's much less likely that that the leak is coming from above that point?