When patching stops being worth it

Daylight or damp in the attic

The attic tells the truth earlier than the ceiling does. Staining on the underside of the deck predates any stain you will see downstairs by a long way.

The age on the paperwork

Age alone is not a reason to replace. Age plus any one of the symptoms above usually is.

Sagging along a line

A ridge or a plane that dips is a structural signal rather than a covering one. It usually means decking that has been wet long enough to lose strength, and occasionally framing. This is the one symptom that should not wait.

Granules in the gutter

The granules are the sunscreen. Losing them in volume means the asphalt beneath is being cooked directly, and from that point the roof ages in years rather than decades.

Repeated repairs in different places

One leak is an event. Three leaks in three different areas inside two years is a pattern, and the pattern means the covering has reached the end of its service life rather than suffered a specific failure.

Shingles that curl, cup or go brittle

Look along the roof from the ground at a low angle rather than straight on. Edges that lift, corners that curl upward and a surface that no longer lies flat all mean the material has lost its flexibility. Brittle shingles crack when walked on, which is why contractors stop wanting to walk them.

In short

None of these on their own settles it. Two together usually do. An inspection costs little and removes the guesswork entirely.