How Velux Replacement Works
A lot of GTA homes have Velux skylights from the 1990s and early 2000s. They were good units, but 20+ years of Toronto weather wears out seals, gaskets and flashing. The good news is that Velux has kept its sizing system consistent, so an old unit can usually be replaced with a current model in the same opening.
We start with the data plate. It tells us the model and size code, which tells us exactly which new unit and flashing kit to order. If there is no plate, we measure the rough opening and match it.
The 4 Velux Replacement Paths
- Same-size, same model for a straight swap.
- Same-size upgrade from fixed FS to venting VS or solar VSS.
- Brand switch from a non-Velux unit to a Velux FCM curb-mount.
- Enlargement to a larger Velux size with reframing.
Residential Velux Replacement
Kitchens
Fogged FS units upgraded to VS or VSS. Older Velux FS units over a cooktop usually fail at the seal first because of the heat and steam. A same-size upgrade to VS manual venting or VSS solar venting adds real exhaust without enlarging the opening, and the swap is usually done by mid-afternoon.
Bathrooms
Failed seals and condensation, upgraded glass. Steam from a shower will fog an old Velux seal long before the rest of the bathroom fails. A replacement lets us swap to current Low-E3 laminated bathroom glass and reseat the shaft to today’s air-sealing standards under OBC 9.7 and 9.26.
Bedrooms
VSS upgrade plus blackout blind. Replacing an old fixed Velux in a bedroom is the cheapest time to step up to a solar VSS venting unit and add a solar-powered blackout blind on the same visit. You get fresh air, true blackout sleep, and a new factory warranty on the whole package, all in one swap.
Stairwells
Hard-to-reach units become solar. Stairwell skylights are the worst to operate with a hand crank because of the ladder angle, so a replacement is the moment to swap the manual VS for a solar VSS with a remote. After the swap you can open and close the stairwell skylight from the landing without a stick or a step stool.
Attics
Multiple units replaced in one visit. If three or four units are on the same slope and were installed in the same era, the seals usually fail within a year of each other. We batch the replacement so the crew, the disposal bin and the flashing kit order happen once, which usually drops the per-unit price by a couple hundred.
Bungalows
FCM curb-mount retrofits on low slopes. Toronto bungalows often have 3-in-12 pitches where the original deck-mount Velux has leaked at the flashing for years. A brand switch to a Velux FCM curb-mount on a rebuilt curb solves it permanently and lets us choose a larger size code while we are at it.
Commercial Velux Replacement
Offices
Like-for-like replacements with minimal disruption. Office tenants cannot afford a week of tarps over the reception desk, so we schedule a same-size Velux swap over a weekend or a single business day. The flashing kit, insulation and drywall are done in one visit and the warranty is registered before the office re-opens.
Condo Buildings
Penthouse and amenity units, board-approved. Penthouse skylights and amenity room units usually require board approval, proof of WSIB coverage and a $5M COI before the work starts. We have the standard paperwork on hand, file the engineer-stamped drawing if a curb is being modified, and only schedule after the board signs off.
Retail
Swaps before opening. Retail skylight swaps usually happen overnight or before a Monday opening so customers never see scaffolding on the sidewalk. The old unit is removed, the new Velux and flashing kit are set, and the interior is sealed and painted before staff arrive in the morning.
Clinics
Laminated replacements over patient areas. Clinics and treatment rooms need laminated glass for safety and to keep rain-on-tin noise out of the appointment. We pair a Velux laminated Low-E3 unit with a sound-dampening shaft detail so the room stays quiet and the glazing meets OBC 9.7 safety standards for overhead glazing.
Specialty Velux Replacement
Curb Adapters
For brand switches onto existing curbs. When you are switching off a non-Velux unit, the existing curb is usually the right size for a Velux FCM with a small adapter. We shim and seal the adapter to OBC 9.26 standards so the new Velux sits flat on the old curb and the flashing kit integrates with the existing roof system.
Solar Upgrades
VSS with rain sensor. If you have been living with a crank rod for twenty years, replacing an old Velux FS with a current VSS solar venting unit is the upgrade that pays for itself. The VSS adds a remote, a built-in rain sensor that closes the glass on the first drops, and no electrician to schedule because the unit powers itself.
Electric to Solar
Replacing failed VCS motors with VSS units when wiring is a problem. Older VCS motors fail before the frame does, and chasing new wire through a finished ceiling is expensive. A same-size VSS swap drops onto the same opening with no electrician, no ESA permit, and you keep the venting function with a remote instead of a keypad.
Blind Add-Ons
Ordered with the new unit. Adding a Velux blackout or heat-reducing blind at the time of replacement costs less than a second visit later because we are already on site. Blackout blinds cut roughly 99 per cent of light for bedrooms and heat-reducing blinds drop summer gain on south-facing slopes.
Replacement Parts and Materials
| Situation | What we use |
|---|---|
| Velux to Velux | Matched size code, new EDL/EDW/EDM kit |
| Non-Velux to Velux | Velux FCM + curb adapter or new curb |
| Upgrade | VS or VSS in the same size code |
| Underlayment | Grace Ice & Water Shield, Velux collar |
Our Velux Replacement Expertise
We have decoded hundreds of Velux data plates and know which older models need adapters. Nine times out of ten, a failing old Velux just needs the new unit and a new kit, not a whole new opening.
What Actually Stops Owners From Replacing an Old Velux
“It’s a Velux, it should last forever.”
In our opinion, 20 to 25 years is a great run for any skylight. Seals and gaskets do wear out.
“They don’t make my model anymore.”
The size code still matches a current model. Velux has kept its sizing system consistent since the 1990s, so a 1998 FS C06 unit still matches a current FS C06. The internal upgrades are usually better glass, a current rain sensor and a refreshed flashing kit design.
“I’d rather just reseal it.”
Fogged glass cannot be resealed. Replacement or a new sash is the fix.
“Replacing means a permit.”
Same-size swaps usually do not need one. A same-size Velux for Velux swap in the same opening is treated as maintenance by Toronto building departments and rarely needs a permit. Enlarging the opening, reframing a truss or cutting a rafter triggers a permit, which we pull as a separate line on the quote.
Velux Replacement Timeline
Data Plate Check
Free assessment. We come out, climb into the attic or open the existing unit, and read the Velux data plate on the sash or frame. From the model and size code we can usually give you a firm replacement price on the spot, before any deposit is taken.
Ordering
One to two weeks. Common Velux sizes ship from the Toronto Velux warehouse in three to five business days, so most replacements are scheduled within two weeks of the data plate check. Specialty glass or colour-matched frames can stretch to three weeks, and we will say so up front.
Swap
Half a day to a day. The crew strips the old Velux, disposes of it, sets the new unit and flashing kit, and reseats the shaft insulation in a single visit. Most same-size swaps in finished rooms wrap by mid-afternoon, with the drywall finished and the room cleaned before we go.
Warranty
Registered fresh. The factory warranty on the new Velux starts the day of install and we register it online before we go. You get the confirmation by email the same day, plus our lifetime leak-free flashing warranty, so a leak in the install is on us for as long as you own the roof.
Velux Replacement Cost in Toronto: What You Are Paying For
New Velux Unit
Matched or upgraded. A same-model Velux for Velux swap runs from $2,500 per unit. Upgrading the same opening from fixed FS to manual VS adds a few hundred, and a step up to solar VSS lands around $4,500 to $6,500 installed because the unit itself is more expensive.
Flashing Kit
New every time. The flashing kit is never reused on a Velux replacement because the gaskets and sealants are designed for a single install. EDL goes on asphalt, EDW on profiled tile or metal, EDM on low-profile materials, and the Velux underlayment collar wraps every install.
Removal and Disposal
Included. We strip the old Velux, drop it into our disposal bin, and haul it away the same day so you are not parking a long trek for the roofer. If the old frame is glued in with old flashing cement we cut it out in sections rather than pry it, which protects the surrounding shingles.
Curb Work
Adapter or repair if needed. Brand switches from a non-Velux unit onto an existing curb use a Velux curb adapter so the FCM sits flat and square. If the existing curb is too rotted to anchor into, we tear it down and rebuild it on site before the new unit goes in.
Upgrade Premium
For VS or VSS. Going from a fixed Velux FS to a manual VS adds about $400 to $1,000 per unit because the venting frame, hinge and operator are pricier. Stepping up to the VSS solar venting unit adds the integrated solar panel, battery and remote, which usually lands around $4,500 to $6,500 fully installed.
Blinds
Optional. Velux blackout, light-filtering and heat-reducing blinds can be ordered with the new unit and installed the same day. Adding them with the replacement visit saves the labour of a second trip and you walk into a finished room that is light and climate controlled from night one.
Velux Replacement vs New Install vs Repair: Which Service You Need
Old Velux, same spot: this page. No skylight yet: Velux installation. Just a leak: flashing repair.
Fixed, Venting or Solar: Choosing Your Skylight Type
Replacement is the cheapest time to upgrade from fixed FS to VS or solar VSS.
Velux Replacement Timeline in Toronto: What to Expect Week-by-Week
Assessment week one, delivery in one to two weeks, swap in a day.
Why Toronto Homeowners Trust Our Velux Replacements
We have been decoding Velux data plates and replacing failed units across Toronto and the GTA for over twenty years and more than 2,000 skylights, certified as Velux Certified Installers since 2004. Every replacement is detailed to OBC 9.7 for the fenestration and OBC 9.26 for the roofing, with a brand-new EDL, EDM or EDW flashing kit matched to the roof you actually have. Every crew is in-house, WSIB-covered and on payroll with us, so no subcontractors touch the opening, and each quote is itemized with the permit (when one is needed) as its own line. You get a fresh factory warranty registered the same day, plus our lifetime leak-free flashing warranty, and pricing is published so the quote is the quote. Trust us, you’re in good hands.
