Skylight Cost Calculator
Choose the skylight type, size and whether you’re replacing an existing unit, cutting a new opening or installing a tubular skylight. The calculator itemizes the unit, flashing kit, labor and interior finishing so you can see where the money goes.
Skylight Cost Calculator
Estimate the cost of a skylight project — the unit, flashing kit, installation labor and interior finishing — for a replacement, a new opening or a tubular skylight.
Your results appear here and update as you change the numbers.
How this calculator works
- Per skylight, low and high: unit price × size factor + flashing kit × roof-material factor + labor hours × labor rate × steepness factor + interior finishing (new openings only).
- Total = per-skylight cost × number of skylights × regional factor.
Worked example
Replacing one medium fixed skylight on an asphalt roof of medium steepness, national average: low $400 + $100 + 4 h × $75 = $800; high $1,200 + $300 + 8 h × $75 = $2,100 (example prices).
When to get a professional check
New openings that cut rafters or trusses need proper framing and may need a permit and an engineer for trusses. Use the manufacturer’s flashing kit to keep the warranty.
Assumptions used — example values, not yet reviewed against current local prices
| Assumption | Value |
|---|---|
| Fixed skylight unit, low | $400 |
| Fixed skylight unit, high | $1,200 |
| Manual venting unit, low | $600 |
| Manual venting unit, high | $1,500 |
| Electric/solar venting unit, low | $1,000 |
| Electric/solar venting unit, high | $2,200 |
| Tubular skylight kit, low | $250 |
| Tubular skylight kit, high | $700 |
| Size factor: small | ×0.8 |
| Size factor: medium | ×1 |
| Size factor: large | ×1.4 |
| Flashing kit, low | $100 |
| Flashing kit, high | $300 |
| Flashing factor: asphalt | ×1 |
| Flashing factor: metal | ×1.5 |
| Flashing factor: tile | ×2 |
| Labor hours: replacement, low | 4 h |
| Labor hours: replacement, high | 8 h |
| Labor hours: new opening, low | 10 h |
| Labor hours: new opening, high | 20 h |
| Labor hours: tubular, low | 2 h |
| Labor hours: tubular, high | 4 h |
| Labor rate | $75 /h |
| Interior finishing for a new opening, low | $300 |
| Interior finishing for a new opening, high | $1,200 |
| Steepness factor: low | ×1 |
| Steepness factor: medium | ×1 |
| Steepness factor: steep | ×1.2 |
Sources and references
Ready for real prices? Learn how to find and vet a local roofer.
How to choose a contractorResults are planning estimates, not quotes. Prices vary by location, contractor and the condition of your roof. Verify sizes and code requirements locally before buying or building.
Frequently asked questions
Is replacing a skylight cheaper than adding one?
Usually much cheaper — a new opening adds framing and an interior drywall shaft.
Should I replace the flashing?
Yes. Use the manufacturer’s flashing kit; reusing old flashing is a common leak source and can void the warranty.
Are tubular skylights worth it?
For small rooms and hallways they bring in daylight at a fraction of the cost, with no drywall shaft.

