Joining Party Wall Roof

[RachelSBM]

Hey all,

We are planning to build a single storey extension (brick built, slate roof) which will adjoin with our neighbour's single storey garden building (brick built, tile roof). We need to use slates due to being in a conservation area, however the neighbour's building pre-dates the designation of the conservation area so uses tiles.

We have had architects drawings and planning approval agreed, but I've only now got to wondering how to join the roofs together. I've seen discussion of parapet walls, bonding gutters, coping walls but I am struggling to really grasp the key pros and cons. The bonding gutters seem the neatest to me, as I think having the flush roofline will look best but I think my neighbour prefers the idea of a wall between to give the delineation?

Thanks in advance for any comments!

 

[catlad]

What pitch is the neighbours roof? will you have enough
pitch to use slate ?

 

[sxturbo]

Bonding gutter.

Absolutely do not do parapet, coping wall etc. These WILL cause you problems likely not straight away but few years down the line you'll have damp problems galore

 

[RachelSBM]

Yes we have enough pitch for slate, the neighbour could have opted for slate at the time but went for tiles as it was cheaper :-/

I had read the concerns re parapet, coping wall etc. It seems that the survival of them is down to building it right in the first place and decent maintenance eg flashing correctly, resolving cracks etc?

 

[sxturbo]

Yes we have enough pitch for slate, the neighbour could have opted for slate at the time but went for tiles as it was cheaper :-/

I had read the concerns re parapet, coping wall etc. It seems that the survival of them is down to building it right in the first place and decent maintenance eg flashing correctly, resolving cracks etc?

Yes, its in the design and building of it.

It is very rare for both to be done properly from experience and research.

They also require regular maintenance or at least keeping an eye on for signs of wear.

Personally I can't stress enough that you shouldn't go this route.

It's just not worth the hassle imo

 

[RachelSBM]

Thanks, I appreciate the input!

 

[^woody^]

We have had architects drawings and planning approval agreed, but I've only now got to wondering how to join the roofs together

What's the Architect's refund policy for not doing his job?

 

[Leofric]

As others imply, ask the architect what they had in mind.

 

[datarebal]

What do the drawings show?

 

[catlad]

Bonding gutter.

Absolutely do not do parapet, coping wall etc. These WILL cause you problems likely not straight away but few years down the line you'll have damp problems galore

I like this! a parapet wall is a poor choice but a bonding gutter with a life expectancy of 15yrs is a good choice.

 

[Leofric]

Presumably a parapet wall would have been apparent on the drawings anyway

 

[sxturbo]

I like this! a parapet wall is a poor choice but a bonding gutter with a life expectancy of 15yrs is a good choice.

not entirely sure where you get your lifetime figures from, everything i see advises a minimum of 30 years. one such example https://www.hambleside-danelaw.co.uk/products/dry-fix-bonding-gutter-low-profile/

a poorly installed parapet has zero lifetime, finding a builder who can build a parapet correctly is very difficult, i've seen more hash ups than good.

anyway as others have said whats on the drawings

 

[RachelSBM]

Hey all,

I appreciate the comments.

The drawings which have planning appfogal don't show a parapet wall between the buildings, so either bonding gutter or they have missed it :-/ I've asked the architect but not had a response just yet (only asked yday and my actual architect has been furloughed so waiting on the big boss to respond). I was interested to get views from people who have the experience of installing/fixing the options so I know if the architects suggestion is what I want to go for.

Thanks!

 

[catlad]

Hi Rachel
There will be a discrepancy between the finished roof heights depending on which tiles where used, I would use a mop roll and lead flash to denote the boundary for a long lasting finish.
Turbo. a life time of roofing has told me these new plastic products don't last as long as they claim, and will fail long before the rest of the materials, especially valleys!
It used to wind me up but its just a sign of the times these days, and why should you design something to last when everyone has a google at the end of their fingers now.
Keeps me busy so it must be good!

 

[Leofric]

and why should you design something to last

- Because that is the correct thing to do