Leaking Roof by Chimney

[Homeowner666]

We had a major house renovation project a few years ago and as part of that we had the roof replaced. The chimney was repointed and crown replaced. Not aware of any leaks at this location prior to the roofing works. The upstairs bedroom had not been redecorated since the 1980s and no evidence of any damp.

The roofer came back several times to check various parts had been correctly installed including flashing etc. Now saying that probably best to rebuild the whole chimney and incorporate a lead tray to stop any water penetration. Due to the size of stack this is sure to cost a lot of money and seems to be a bit of a wild stab in the dark. First photo is just before the roof was completed. The other two photos are in the roof void.

If anyone has any ideas as to how to remedy I would be very grateful. Many thanks

 

[Terrywookfit]

A picture of the flashings would help.

 

[Homeowner666]

Hi Terry, many thanks for your reply please see the attached photos if that helps.

 

[Homeowner666]

Here is upstairs bedroom...

 

[Terrywookfit]

Have individual soakers been fitted to each coarse of tiles

 

[Homeowner666]

Hi Terry, thanks for reply .

The quote for the chimney stack part from roofer.

a) Carefully remove all lead/zinc flashings and clear.
b) Cut tiles neatly around chimney using tiles and halves as required.
c) Fabricate Code 4 lead apron flashings with lead welded corners.
d) Dress Code 4 lead soakers neatly over tiles with 100mm upstands.
e) Fabricate Code 5 lead back gutter with lead welded corners. And dress over existing timber layboards on a Geotextile lead underlay.
f) Form new chase in abutment brickwork and install Code 4 lead cover flashings tucked into brick joint and wedge in position before sealing with Calder lead sealant.

We had our general builder (not a roofer but will install roof as part of extension etc) take a look a couple of years ago, he thought it all looked like a good job. He checked under a few tiles as much as he could and thought it all looked good. Said the leadwork looked very good with joints properly soldered etc. He installed a chimney cap as was open before.

I didn't specifically ask about individual soakers but presume that if on the quote fingers crossed they have been installed (and correctly).

Thank you, appreciate your help.

 

[Terrywookfit]

The Back gutter looks very suspect !!

Have the tiles slipped onto the sole board.
How high does the back gutter go up the tiles.
There will be Lots of water hitting the back of that stack

 

[Harry Bloomfield]

Why the misalignment in the row of tiles, in this photo?

https://www.diynot.com/diy/attachments/photo-2022-03-23-18-52-10-copy-jpg.321433/

 

[Homeowner666]

Many thanks for your replies . I am not sure about the misaligned roof tiles. Had presumed this happened when the builder (now retired) was checking underneath the tiles but thought he had reinstalled them afterwards as they should be.

I am not sure now high the back gutter goes on the tiles and I suppose there is no way of knowing for sure without removing the tiles and checking. Is there a British standard / calculation for working out how high up it should go? for example working out height of roof/ pitch of slope / type of tile etc. I agree that would be a lot of water hitting the back of stack. If it’s the same as the front of the stack (apron?) that looks approximately a tiles length which would be asking quite a lot.

Thinking about it I suppose the very first photo I posted on the thread may indicate how far up the back gutter goes. Many thanks for your help.

 

[tomm12]

its a puzzle but i think the back gutter and the membrane are somehow at fault.
The back gutter should slope a little towards the chimney but its sloping the other way.
The sheets of membrane seem to have been pieced in above the back gutter.
The membrane should have been run past the trimming & back gutter boards and come up as an upstand at the chimney but we obviously cant see if that detail was done correctly?
From higher up water could be tracking down the membrane under the tiles but the upper tiles look OK.
I think it needs the back gutter lead and surrounding tiles to be lifted for a better investigation.

Attempts have been made to seal the cracks in the flaunching but maybe rake them out again and seal them again. Same with the pots.

Otherwise the leadwork looks great and the tiles seem well done.

 

[Homeowner666]

Many thanks for your reply Tomm12. As you say I will arrange for the tiles and back gutter lead to be taken off and get the area inspected. The roof is still under guarantee so will try and get them back to have a look. Hopefully they will be willing.

He may say again about rebuilding the whole chimney with a lead tray incorporated but I am sure this is a red herring.

 

[tomm12]

The chimney stack lacking a lead tray, if it is missing, is not the problem.
I dont know if anyone has mentioned but if you cant get on the roof. with the roofers then ask for pics of when the lead and tiles are lifted

 

[Homeowner666]

Thank you, very helpful advice. Will let you know how I get on.

 

[noseall]

The Back gutter looks very suspect !!

What looks suspect about the back gutter?

 

[datarebal]

This guy knew what he was doing . I'd be amazed if he omitted soakers. If he had the roof shield would show somewhere .
It should have a tray , unless of course you have a fire burning on a daily basis.
A couple of tiles need a pull down but unlikely the cause