Raising eve height /shortening rafters

Hi, not the easiest to explain but looking at extending where the existing elevation is stepped outwards and the roof continues down to a lower eaves height which would need to be raised to provide standard ceiling height on first floor extension.
The approach I was thinking would be to cut New wall plate further up existing rafters level with correct ceiling height, birdsmouth the rafters in situ and sit this on top of a steel beam bearing onto existing masonary at each end. Then knock out existing wall (about 600mm further down the rafters) and cut rafters short to allow standard ceiling height.
The roof plane being supported will be stripped and have extension rafters and lay board bearing off it.
Sorry if it's a bit vague but just after an idea if anyone's ever come across this as it's early days
Cheers
John

Why not scan a sketch of your proposal or a relevant bit of the BCO approved plans?

Yes, I have come across stuff like this.

When a building steps out and the roof continues in the same plane and has to meet the step out wall lower down.

Yes that's it, I want to raise the eave to the higher level and cut a hipped roof off the side, house is a 30s semi. the stepped out section will be knocked out as the bigger extension is built around it
Cheers
John

Thanks for the reply and drawing noseall, does my explanation at the top make any sense as I would be keen to know how you tackled it.
Not got any drawings or even planning yet just trying to work out what's likely to be involved and any obvious complications!
Cheers
John

23vc said:

Thanks for the reply and drawing noseall, does my explanation at the top make any sense

Click to expand...

Makes perfect sense. It may be difficult to cut your b/m's in situ, but not impossible. A simpler solution may be to use truss clips.

If you do decide to b/m the rafters, then you may be able to offer the wall plate into position and fix it to the rafters. You can then offer the beam up to the underside of the plate (complete with holes drilled into the web) and fix it to the wall plate, whilst Acrow propping from below. The beauty about this method is that you can faff about with the loose wall plate, offering into place and seeing where you may need to trim the odd b/m here and there.

Brilliant thanks again. Truss clips is a good shout thanks