Damp patch coming in at next doors roof level

[chriselevate]

Can you spot if the following pics are likely to be causing this damp patch on the inside of my beautifully newly plastered hall way?! If we get more than 4 hours rain then the patch appears.

Unfortunately the scaffolding that was up to redo the lead valley has now been taken down so the access to this area is now very difficult. I think the scaffolding will need to go back up in order to fix it!!!

Please could suggest what you would do to dress it all down so that it wont cause the damp problem in future? Thanks.

 

[KenGMac]

chriselevate, Hi

From what I can see on the photos?

I for one do not like, SORRY! about that. In my opinion, the lead has been dressed in-correctly, in that the lead should have formed a "secret gutter" where the tiles are removed, the lead is then dressed outward from the parapet / party wall, on top of the under-slate roofing felt to then be dressed up and over a batten fixed down the slope of the roof?

See for instance http://www.britishlead.co.uk/downloads/fitting-guides2.pdf
look at the detail for a "Secret Gutter" there are other sites for detailing lead and slates, have a look?

Again in my opinion what is probably happening is that rain water is running down the tile. the rain can and will track "sideways" especially at the bottom of the higher tile and the interface of the lower tile, this process can and is assisted by the action of the wind, to end up dripping off the edges of the tile adjacent to the party wall / Parapet. Once in this position the rain water can cascade into the masonry of the wall and hence the damp marks in your photo.

it is highly "Probable" that the rain water is being "drawn" by capillary action "sideways" along between the tile and the underside of the Lead, this can only cause more rain water to end up in the same position as last paragraph.

On another front, the "up stand" above the flashing appears to be a painted on material? its colour has the appearance of lead but is not lead.

I for one would do some research on the Web, look at the "Contract" between you and the Roofer then call him back for a "CHAT?"

In all as far as I can see, the dressing of the Lead is far from what I would expect to see.

Lets see if anyone else in here concurs? just in case I am very in-correct?

Ken

 

[Bosswhite]

Looks like its a bit of a bodge job,
Picture three looks like the builder has put "Flash Band" instead of Lead Flashing and then painted it with grey undercoat to give the appearance of lead.
Get a second opinion from another builder then proceed from there.

 

[Burnerman]

Can you give us another shot with the pallet / scaffold board out of the way?
John

 

[chriselevate]

Thanks for the input so far guys.

Do these additional shots help?

This one for context:

This one for close up:

 

[Burnerman]

That flashing needs to come up the wall and be chased in.....it looks like a readily leaking channel there to me!
A quick fix could be a sand / cement fillet connecting the wall to the flashing, but it sure is a bodge, that one.
John

 

[chriselevate]

Thanks John. So it's obvious from the pics that it's going to be causing a damp patch inside the house thdb?

What are the steps to fix this then? Eg.
1. Rip out and throw away old lead to the length of the roof
2. Disc cut a slot on the house
3. Etc etc


Does it look a big and expensive job once the scaffold is up?

 

[Burnerman]

Certainly I don't think you need to look much further damp wise!
Ideally the first row of tiles needs to come off, and a lead flashing installed - going up the wall into a chased groove.
John

 

[Bosswhite]

The gutter by the first bracket seems to be blocked with weeds,

the rain could be running down the flashing into the gutter and overflowing, its difficult to tell with the photo but at the "end stop" of the gutter there seems to be a black mark which suggests it may be a hole in the rendering, and the middle tile dosent seem to be bedded down very well, there is algae between the rendering and flashing which suggests a gap