How long does it take to replace a skylight?
Short answer. Replacing a skylight with a same-size unit usually takes a roofing crew a few hours to one day, including removing the old unit, checking the curb and framing, installing the new skylight and flashing kit, and reshingling around it. Changing the size, building a new shaft, or repairing rotted framing and interior drywall can stretch the job to several days.
A typical same-size replacement
- Protect the room below and remove the shingles around the skylight.
- Remove the old flashing and unit.
- Inspect the framing, curb and deck for rot and repair as needed.
- Set the new skylight square and level.
- Install underlayment and the manufacturer's flashing kit, weaving step flashing into the shingles.
- Reshingle around the unit and clean up.
- Inside, check the trim and seal; drywall repairs may be a separate step.
What makes it take longer
- A size change. Cutting rafters or adding headers is carpentry and may need a permit.
- A new shaft or interior finish. Drywall, mud, sanding and paint need drying time between coats.
- Rot. Water-damaged curbs and decking add time.
- Special orders. Uncommon sizes or venting units may need to be ordered in.
- Weather. The roof is open during the work, so crews wait for a dry day.
Doing it with a reroof
During a full roof replacement, a skylight swap adds relatively little time because the shingles around it are already off. That is the most efficient time to do it. See replacing a skylight with the roof and what to expect on roof replacement day.