The longer answer
The sequence, done right:
- Gutter comes down carefully — sections marked, hangers saved or replaced.
- Rotted fascia comes off; sound wood behind it gets inspected while it's exposed (the only time anyone can see the rafter tails).
- New board goes on — pressure-treated wood or cellular PVC, primed and painted to match.
- Gutter goes back up at the correct pitch, with hangers screwed into fresh wood at proper spacing.
Where split-trade jobs go wrong: a carpenter who doesn't hang gutters re-installs them flat or back-pitched, seams get stressed, and the first storm overflows — onto the brand-new board. We see the results on repair calls constantly.
When to do both at once: if the gutters are older or failing anyway, replacing them while they're already down saves the second mobilization — full tear-off and new seamless install typically runs $1,400–$4,000 for residential, and every replacement includes a fascia inspection with rotted-board replacement priced before work starts.
Details: fascia replacement & repair · gutter replacement.