Built-in gutters, flashing and the hidden parts of an old roof
Some older houses have built-in or box gutters tucked into the roof edge, lined with metal that wears over time. When these fail, water can run down inside the wall before anyone sees it. Chimneys are another trouble spot, often tall, brick and surrounded by flashing that has been patched more than once.
Under the surface, old decking may include wide boards with gaps, which behave differently from modern sheets. Where leaks have run for years, the wood can be soft. These hidden parts are why a careful inspection matters here, and why a quote should include a note about what could be found once the old roof comes off.
