I am replacing a slate roof and its structure on an outbuilding ( approx 4.5 Sq m). The building is over a hundred years old and the roof adjoins the neighbours outbuilding of the same size.
The size of the slate removed is 570mm x 310mm and the nearest size available of replacement slate (natural or fibre cement) is 600mm x 300mm.
The problem is, taking into consideration the length of the slate and the nail hole positions I don't expect a 600 x 300 will interlock with the original slates 570 x 310 which are still on the adjoining property.
If the 2 different slate sizes can't be interlocked is there some sort of simple straight abutment method I could use which is not interlocking but would create a seal?
