01 — The problem
Water that can’t get away runs down the wall.
That is the whole job. A blocked or undersized gutter saturates the render, finds the cavity and rots the rafter feet. By the time you can see it from the pavement, the timber behind the fascia has usually been wet for years.
Saturated renderRotten rafter feetInternal staining
02 — The fix
Full-depth board, not a 9mm cap.
Capping thin plastic over rotten timber hides the problem for about five years. We strip back to the rafter feet, check what is actually there, and fit an 18mm full-replacement fascia the gutter can be screwed into properly.
18mm fasciaRafter feet checkedNo cap-over
03 — The detail
Vented, so the loft can breathe.
Modern roofs need airflow at the eaves or condensation forms in the loft and soaks the insulation. A continuous 10mm vent goes into the soffit, and a felt support tray makes sure water off the felt actually reaches the gutter.
Continuous 10mm ventFelt support trayDeep-flow option