Terraced house neighbour has replaced their roof and left rear roof join like this...

[David_]

Hi

I live in a terraced house - my roof was replaced with Eternit slates by the previous owner in 2011 before I bought it.

My neighbour has recently replaced their roof without prior notice / discussion.

The join between our roofs on the front appears to have a GRP bonded gutter.

The join between our roofs on the rear does not have a GRP bonded gutter and does not look right to me.

As you look at the photos below of the rear of our terraced houses - my house is on the right. The new roof is on the left.

Here's a photo I took 1-May-2026 of where our roofs join at the rear:

20260501_175523.jpg

• David_
• Today at 12:02 PM

And a close up (also taken 1-May-2026) of the mortar that has been used instead of lead flashing:

20260501_175536.jpg

• David_
• Today at 12:04 PM

I've been back up and had another look today (10-May-2026) - and there's a lot of old slates just behind the chimney on my roof - which don't show in the photo above:

20260510_110038.jpg

• David_
• Today at 12:06 PM

And I got a couple more photos of where the roofs (don't!!) meet:

20260510_105612.jpg

• David_
• Today at 12:05 PM

Including this one with a tape measure near for scale (the gap looks like a couple of inches to me):

20260510_110235.jpg

• David_
• Today at 12:18 PM

I'm concerned that there is a large gap / void between our two roofs now over the party wall, and I can see the membrane.

The roofer has told the neighbour that they what has been installed is a flat gully. Am I missing something? Is this what a join between two terraced roofs is supposed to look like?

Appreciate any input / advice you can offer.

Thanks,
David

 

[Tetrarch]

First things first. Show your neighbour these photos...

What do they think?

Tet

 

[David_]

First things first. Show your neighbour these photos...

What do they think?

Tet

The situation is complicated by the fact my neighbour is actually a tenant running a business from the premises, but they are not "on premise" very often so I've only been able to exchange information via email. During this event they told me they were a tenant, but for some reason they have not given me the landlord's details (despite 4 requests via email). The landlord arranged for the roof to be replaced.

I shared the photos from 1-May with the tenant, which was when the roofer told the tenant they had installed a flat gully. The roofer is offering to replace this with a different gully "at my request". But I'm concerned with the quality and competence of the roofer, and this shouldn't be "at my request" - either the job has been done to the appropriate standards or it hasn't.

I've asked for more details of exactly what sort of gully is being offered, no reply yet.

I have asked for details from the tenant or landlord of the roofer and their accreditation / professional membership / qualifications etc., as well as asking about building control due to replacing slate tiles with much thicker and potentially heavier slates.

I've looked at other roof joins along the row of terraced house I live on, and I can't see anything like the gap/void on the rear roofs left with my roof.

David

 

[Deluks]

It's very very bad.

 

[^woody^]

It's very very wrong.

That was not done by a roofer.

 

[Si_]

That's the worst thing I've set eyes on this week. Jesus wept.

And beyond the obvious criminal atrocity of the whole thing, it looks like the peculiar leadwork towards the top of that gap actually feeds underneath the membrane half way down.

 

[David_]

Thanks folks. Good to know that I haven't missed something and it's not supposed to look like that. Bad to know that my roof has been damaged.

 

[David_]

That's the worst thing I've set eyes on this week. Jesus wept.

And beyond the obvious criminal atrocity of the whole thing, it looks like the peculiar leadwork towards the top of that gap actually feeds underneath the membrane half way down.

Can you imagine how I felt at the top of my triple extension ladders when I spotted it!