Replacing a skylight in the Seattle area costs $1,900 to $3,800 per unit when the work happens during a roof replacement, and $2,500 to $4,900 per unit as a standalone project. The gap exists because a reroof already pays for the tear-off, the flashing work, and the crew being on your roof. If your skylights are more than 15 years old and a roof replacement is on your horizon, bundling the two is the single easiest way to save money on both.
Here is how the numbers break down for King County homes in 2026, and how to decide whether your skylights should be replaced now, during your next reroof, or not at all.
Skylight Replacement Cost by Scenario
| Scenario | Cost per unit, installed |
|---|---|
| Fixed skylight, replaced during a reroof | $1,900 to $2,700 |
| Vented skylight (manual or electric), during a reroof | $2,400 to $3,800 |
| Fixed skylight, standalone project | $2,500 to $3,600 |
| Vented skylight, standalone project | $3,000 to $4,900 |
| Cutting a brand-new skylight opening | $4,500 to $8,500 |
These are installed prices: unit, flashing kit, underlayment integration, and labor. Interior drywall or light-shaft repair, when needed, typically adds $300 to $900.
Why Replacing Skylights During a Reroof Costs Less
The discount is not a promotion. It is real work you avoid paying for twice:
- Tear-off is already included. The shingles around your skylight come off during a reroof anyway. On a standalone job, that removal and rebuild is billed separately.
- Flashing integrates into the new roof system. A skylight replaced mid-reroof gets its flashing kit woven into fresh underlayment, which is how manufacturers intend it to be installed. Retrofitting flashing into an existing roof takes longer and relies on more sealant.
- One mobilization instead of two. Staging, ladders, safety setup, and disposal are shared with the roofing project.
- Curb and deck problems get found once. Rot around a skylight curb is common on homes near tree cover. During a reroof, the deck is already exposed, so the repair is a line item instead of a surprise.
- The warranty lines up. A new roof with 20-year-old skylights has a weak point the roof warranty does not cover. Replacing both together means the entire system ages on the same clock.
The Age Math: Why 2026 Is Catching So Many Skylights
Most skylights last 20 to 25 years in the Pacific Northwest. The install boom of 2005 to 2010 means a large wave of King County skylights is reaching end of life right now, often on the same houses whose roofs are also due. The signs they are done: fogging between glass panes, hairline cracks at the corners, staining on the interior shaft, or any active drip.
One number worth knowing: a failed skylight rarely announces itself with a dramatic leak. It weeps slowly into the framing around the curb, and by the time the ceiling shows a stain, the repair usually involves carpentry, not just glass.
What Moves the Price
- Glass package. Laminated, low-E, or rain-sensing glass adds $200 to $700 per unit over standard tempered dual-pane.
- Size and model. Common deck-mount sizes are the ranges above. Oversized or curb-mount conversions price higher.
- Roof pitch and access. Steep pitches and limited staging add labor.
- Venting and controls. Electric openers, remotes, and rain sensors push a unit toward the top of its range.
- Interior finish. A skylight with a deep drywall shaft costs more to trim out than one in a vaulted ceiling.
When Not to Wait for the Reroof
Bundling saves money, but three situations justify a standalone replacement now: an active leak, fogged or cracked glass on a skylight over a living space, and any unit older than 25 years on a roof that still has 5 or more years left. Water damage compounds monthly. The savings from waiting two years for a bundle disappear with one soaked ceiling.
How Prosperity Handles Skylights on a Reroof
Every roof replacement quote we write lists skylight replacement as its own line item, priced per unit, so you can decide with real numbers instead of a lump sum. As a GAF Master Elite contractor, we integrate skylight flashing into the same system that backs the Golden Pledge warranty, and our crews photograph the curb framing before closing anything up. If a skylight is genuinely fine, we say so and reflash it instead.
Want to know what your skylights would add to a roof project? Call (425) 448-5556 or request a free inspection. You get a line-item quote, not a guess.
Frequently Asked Questions
Should I replace my skylights when I replace my roof? In most cases, yes. If the skylights are more than 15 years old, replacing them during the reroof costs $600 to $1,100 less per unit than doing it later as a standalone project, and the new flashing integrates into the new roof system. Skylights under 10 years old in good condition can usually be reflashed and kept.
Can a roofer replace a skylight? Yes, and for deck-mounted skylights a roofing contractor is usually the right trade, because the job is mostly flashing and waterproofing rather than glazing. Ask whether the installer uses the manufacturer flashing kit and integrates it with the underlayment, which is what keeps the warranty intact.
How long do skylights typically last? 20 to 25 years in the Pacific Northwest. Seal failure shows up as fogging between panes, and gaskets and flashing age at roughly the same pace as an asphalt roof, which is why the two are often due together.
Do all skylights eventually leak? Modern deck-mounted skylights installed with the manufacturer flashing kit rarely leak during their service life. What fails is age: seals fog, gaskets harden, and 20-plus-year-old units start weeping at the curb. Most “leaking skylight” calls we take are actually failed flashing or condensation, both fixable.
Can I replace a skylight without replacing the roof? Yes. Standalone replacement runs $2,500 to $4,900 per unit installed. The roofing around the skylight is opened locally and rebuilt with new flashing. It costs more per unit than bundling with a reroof, but it is the right call for leaks or fogged glass that cannot wait.
Is it cheaper to replace a skylight or remove it? Removal, decking over the hole, and matching the shingles typically runs $1,500 to $3,000, so it is not dramatically cheaper than replacing during a reroof. If you like the light, replacement is usually the better value. Removal makes sense for redundant units or chronic problem locations.
