Sandstone gutters depth

[seasickstevie]

My old property has gutters formed in sandstone and lined with lead.
Problem is, they're just not deep enough and next to no fall towards outlet.

I'm going to remove the lead and build up the edge of the sandstone to give more depth and then replace the lead with new.

I'm looking for any suggestions as to what I should use to build it up.

I thought the best solution may be to shutter the front and insert some plastic 150mm pipe within the gutter, then fill with concrete (then remove later).

Problem is the bay is semi-circular, so could be a problem with the pipe theory.

Any better ideas?

 

[seasickstevie]

I've just re-read my post. Perhaps it sounds like I was intending to fill the pipe with concrete

No - I was thinking of making, in effect a mould with the pipe, and then remove to give the standard half-round shape in the concrete.

I think perhaps some thick tiles cemented either side should do it.

Any better ideas guys?

 

[Deluks]

erm no. Tricky one. Do you live in a castle?

 

[seasickstevie]

No - no castle, just fairly typical 19th century large 3-storey Conservation area type property. Liverpool's got shed-loads of them.

Just that my gutters don't seem as deep as they should.