Rafters and external Leaf

[Ben Mo]

Hello

Im doing a lean to single story extension in England.

Im working on the roof rafters but not sure how best to do the detail where the rafters and external leaf meet.

The outter leaf is very close to the boundary with my neighbour and therefore I cannot have an overhang, it needs to be flush with the wall I assume?

Do I ladder the end rafter to be in line with where the external leaf will go so the roof battens rest on it, or should the blockwork be done to such a height that the battens rest on that? The cavity gap is 50mm as the superstructure is timber framed.

Thanks for any comments

 

[23vc]

Surely your top roof has a gutter overhang so this one can have a couple of inch verge overhang?
Pitch looks shallow but may just be camera angle

You don’t want a ladder, last rafter stays on inside against inner skin, the battens over sail both skins and trap some undercloak or have dry verge …

 

[Ben Mo]

Thanks 23vc

Ah yeah good point about the gutter bit, although for us its a flat roof on that part and its flush up.

The pitch is fairly shallow at about 16.5 sadly. ill have a look into the undercloak abit more

Much appreciated

 

[Ben Mo]

I have included a link to a video with more detail

New video · Friday, Apr 10

Tap to view!

photos.app.goo.gl

 

[noseall]

The pitch is fairly shallow at about 16.5 sadly. ill have a look into the undercloak abit more

As long as the roof isn't overly complicated, 16.5 degrees isn't a bad fall. Marley Mendips go down to 12.5 degrees (with caveats). You won't need under-cloak if you fix dry verge units.

 

[Ben Mo]

The Mendips look nice

 

[noseall]

The Mendips look nice

They are a great tile to work with too.

 

[23vc]

I mendip’d mine, mine was also fairly shallow but was at least 17 for the velux’s. dead easy tiles to lay unlike the Anglias on the upper roof which were horrible.

 

[noseall]

The Mendips look nice

Conv2

• noseall
• 6 Feb 2022

Key

• noseall
• 12 Feb 2022

 

[noseall]

I mendip’d mine, mine was also fairly shallow but was at least 17 for the velux’s. dead easy tiles to lay unlike the Anglias on the upper roof which were horrible.

View attachment 412450

Anglias are one of the worst to work with.

 

[Ben Mo]

I need to keep on with the existing on the roof to looks like Mendips are out.

Looking at the sandtoft 20/20 as an option now.

Had a brickie come round to have a look at doing the walls and he's suggested building up to the same height as the top of the rafters and fly the battens over too.