Rusted box gutters

[JGFG]

a metal box gutter 5m long, between my asbestos garage roof and neighbour is rusted and its leaking water into both garages, impossible to replace without removing large part of roof, any suggestions for painting/covering gutter, read about isoflex etc,
thanks

 

[Diy guy]

Hi I have metal gutters on my house and I had a problem and believe to have fixed it with sylglas waterproof tape. It’s a fabric tape that’s incredibly sticky and can use it to line it while being quite cheap. Have a google and can find find it for about £15 from most shops.