I'm looking into building a 'lean to' conservatory onto single storey
cottage (cca 1800 build), effectively in the corner between the
original building and an extension. The guttering downpipe runs down
this corner and I think my best solution is to move this along the
cottage wall to where the end of the conservatory will be. The matter
of where this pipe drains to is dubious at the moment so re-organising
the drainage is required anyway.

The question concerns the CI guttering which is held in place with
straps going under the slates onto the rafters. How is the slope of
the guttering arrived at with these straps and what will be my
procedure for re-arranging it ?

A secondary question is whether I'm trying to make it more complex for
myself if I try to avoid having two downpipes and run the house outlet
to the downpipe for the conservatory gutter ?

Thanks
Rob