Should You Replace Your Skylight When Replacing Your Roof?

If you are planning a roof replacement in Richmond or the Lower Mainland, make a decision about your skylights before the roofing work begins. Keeping a sound unit may be reasonable, but an older or troublesome skylight deserves a closer assessment while the surrounding roof is being planned.

The useful question is not simply “How old is it?” It is whether the skylight, its glazing and its connection to the new roof can provide dependable service together. Here is how to compare keeping, repairing and replacing it without assuming that every stain means a new skylight.

Why discuss skylights before the roof estimate is final?

A skylight is part of the roof assembly, not just a window placed on top. The installation has to work with the surrounding roofing material. VELUX’s reroofing guidance recommends considering replacement during roof work because the projects can be coordinated.

That does not mean every skylight must be replaced, or that combining the work guarantees a particular saving. Ask for the skylight scope as a separate line in your estimate so you can understand the choice. Decide before materials are ordered, rather than waiting until the crew has opened the roof around it.

First, identify what is actually wrong

Moisture on the room-side glass

Surface condensation is different from rain getting through the roof. VELUX’s maintenance guidance points to ventilation and indoor humidity as important considerations when condensation forms on glazing.

Note whether moisture appears after showers or cooking, during cold weather, or specifically during rainfall. These observations help the assessment, but they do not prove the cause. Replacing the unit should not be presented as a guaranteed cure for an unresolved indoor moisture problem.

Fog trapped between panes

Clouding inside an insulated glass unit is a different issue. The VELUX FAQ explains that fogging between panes can result from a failed glass seal. It also notes that replacement glass or a replacement sash is available for many models.

Ask whether a compatible part is available for your exact skylight and whether the rest of the unit is worth retaining. A glass problem does not automatically establish that the entire roof connection has failed.

Rain-related staining around the opening

Have the skylight and the surrounding roof details assessed together. Flashing is the system that directs water around the opening. VELUX’s flashing guidance shows different systems for different roofing materials and installation conditions.

Ask the contractor to explain whether the proposed work addresses the glass, frame, flashing, supporting curb or nearby roofing. A recommendation to “reseal everything” is less useful than a clear description of the defect and the intended repair.

When might keeping or repairing it make sense?

Keeping the unit is worth discussing when an assessment finds it sound and suitable for the planned roof system. A targeted repair may be an option when the problem is limited and compatible parts are available.

Request written answers to three questions:

• What was inspected, and what condition was found?
• Which existing parts will remain, and which will be renewed?
• What limitations or exclusions apply to the retained skylight?

If the proposed repair only addresses one symptom, ask what remains uncertain. You should be able to compare the actual work offered, not just the final price.

When should replacement be considered?

Replacement deserves a closer comparison when there are several unresolved problems, suitable repair parts cannot be sourced, or the existing unit is unsuitable for the planned installation. A wish to change from fixed glazing to an opening skylight is also a separate product decision, not merely a leak repair.

Mounting type matters. VELUX’s selection guide distinguishes deck-mounted skylights, installed at the roof surface, from curb-mounted units that sit on a raised support. The replacement needs to suit the opening, roof and manufacturer’s instructions—not just look similar from inside.

What should the skylight quote include?

Ask for enough detail to compare like-for-like proposals:

• The proposed manufacturer, model, glazing and fixed or opening operation.
• Whether the existing opening and curb will be retained or altered.
• The flashing and surrounding roofing work included.
• How any concealed damage will be documented and priced before extra work proceeds.
• Removal, disposal, access equipment and protection of the room below.
• Whether interior drywall, trim, painting, blinds or electrical work are included.
• The applicable product and installation warranty terms, provided in writing.

Do not assume a roof warranty automatically covers a retained skylight. Ask how responsibility is divided if a problem appears later.

Common questions

Can I wait until the skylight leaks?

You do not need to wait for a leak to request an assessment. If a roof replacement is already planned, ask for the skylight’s condition and options to be documented now. If water is actively entering, report that when you contact the contractor rather than treating it only as a future upgrade.

Can you assess it from photographs?

Photographs help start the conversation, but they may not show the roof connection or concealed materials. Send indoor photos, any existing paperwork and the model information if safely accessible. Do not climb onto the roof to collect measurements or a serial number.

Plan your roof and skylight work together

Level Up Canadian Roofing & Exteriors provides skylight repair and replacement and roof repair and replacement in Richmond and the Lower Mainland.

Request a free estimate or call 604-239-5656. Include your property address, the number of skylights and whether you are planning roof work or investigating an existing problem.

Featured photo: a Columbia skylight with metal flashing on an asphalt shingle roof.