The roofer asks about the skylight just as you thought the big decisions were finished. It does not currently leak, so keeping it sounds sensible. It is also old enough that nobody remembers its model. Start with that missing information rather than accepting an automatic replacement or an automatic reuse.
Identify what is in the roof
Collect the product label if safely accessible, installation history, service records and photographs. Note whether it opens, whether the controls work and whether clouding is inside the glazing. Record rain leaks separately from winter condensation. A stain in the shaft can have more than one cause.
VELUX's replacement guidance distinguishes curb-mounted and deck-mounted measurement routes and explains the role of model identification. Its published process coordinates the unit, flashing and underlayment. Those are useful planning principles; the dimensions and kit must come from the actual product selected for your Canadian installation.
Ask the installer to verify measurements rather than ordering from visible glass size. The replacement must suit the opening, roof pitch and mounting arrangement. A nominally similar skylight can still change the curb, shaft or trim work.
Compare two complete alternatives
The retain option should identify the condition assessment, compatible flashing work and any limitations when the surrounding roofing is replaced. The replacement option should identify the new unit, kit, opening changes, installation and making good indoors. Ask which warranties apply to the completed arrangement in each case.
Ask whether each quote includes removing the existing layers. The overlay-versus-tear-off comparison explains what inspection access and repair scope you give up when old roofing stays in place.
| Item | Retain | Replace |
|---|---|---|
| Unit condition | Assess frame, glazing, operation and remaining serviceability | Specify exact new model and features |
| Roof connection | Confirm compatible renewed flashing detail | Match kit, underlayment, pitch and mounting type |
| Opening and finishes | State what remains and what may be disturbed | Include curb/shaft adjustments and indoor restoration |
Do not let 'replace while we are there' become a substitute for a price. Request the incremental cost while reroofing, then ask what a later replacement would disturb. Coordinating access may be worthwhile, but there is no honest universal payback without knowing the unit and installation.
Separate a leak from condensation
A drip during a cold spell may involve indoor moisture, air leakage or the shaft insulation rather than failed exterior flashing. A leak during wind-driven rain may lead to another investigation. Give the installer dates and weather conditions, not only a photograph of the ceiling mark.
Use the winter skylight-drip guide before assuming a new skylight alone resolves every symptom. If the roof below has no accessible attic, cathedral-ceiling planning may belong in the same project. The room-side and roof-side details need to meet.
Decide how the skylight will be used
For an opening unit, try the controls and consider reach, insect screening and cleaning. Ask about power, rain-sensing features and service access for the exact model. A new operating feature should solve a household need rather than arrive as an upgrade nobody can comfortably use.
Review the shade arrangement as well. Replacing a unit above a bedroom or television can change glare and morning light. Confirm which shade fits and whether its controls are accessible. Keep these choices in the model schedule so a last-minute substitution does not quietly remove a feature you expected.
Name the interior repair boundary
Ask whether the shaft lining, ceiling paint and surrounding trim will remain. If the opening changes, request a sketch of the finished interior. Include protection for furniture beneath the work and responsibility for plaster or drywall damage. The roof crew may complete a watertight installation while a separate trade still owes the room its finish.
VELUX's skylight replacement overview encourages coordinating replacement with reroofing. It is manufacturer advice, not a requirement to replace every serviceable unit. The homeowner's decision should account for condition, compatible details, desired operation and the cost of repeated access.
Document before the shingles hide the connection
Ask for photographs of the opening condition, repaired substrate and installed flashing/underlayment at the relevant stages. Keep the exact unit and kit codes, installation instructions and warranty documents. The roof quote flashing scope helps identify what should be explicit in the roof scope.
At handover, operate the skylight and shade, check the indoor finishes and confirm any remaining work. Watch the original complaint through relevant weather afterward. A well-timed replacement is valuable when it delivers a complete roof connection and a usable room, not just a newer piece of glass overhead.