Lead flashing advice

[festive]

Due to budget constraints im attempting to do as much roofing work myself.
Ive just felt n battened this area, but am not quite sure how you cut in the lead flashing down the side of my dormer extension over my interlocking concrete tiles. Any pointers most appreciated.

 

[justlead1]

Hi. On tiles you will need to lap 200mm on tiles and 100mm upstand, under what ever material you are using for the dormer cheeks. If you are completing the cheeks first ( allows better access) lay a spare bit of batten up the roof on edge. This will give you the line for the bottom edge of the flashing, fix lead so it sits on the batten. Once you finish the cheeks, remove batten,the tiles will slip under the sheet lead then dress lead to suit. Max length of sheet lead 1.5m for code 4 the lap the next length 75mm measured vertically. Good luck