What Is VELUX Skylight Systems and Model Codes?
A VELUX skylight model code answers two questions: how the unit meets the roof, and how it operates. Deck-mounted skylights fasten directly to the roof deck for a low profile and use the FS, VS, VSE, and VSS families; curb-mounted skylights sit on a raised frame (a curb) and use FCM, VCM, VCE, and VCS. The letters track the operation ladder. Fixed units (FS deck-mount, FCM curb-mount) never open — the FCM has no designated top, bottom, or sides and can be installed in any direction. Manual 'Fresh Air' units (VS, VCM) open with a smooth turning handle in reach or a control rod out of reach. Electric 'Fresh Air' units (VSE, VCE) open at the touch of a button using a single 20-foot hardwire to a standard junction box, and close automatically via a rain sensor. Solar powered 'Fresh Air' units (VSS, VCS) use a small solar panel that charges a battery-powered operating system, so no wiring is required, and an acoustic rain sensor closes the skylight at the first sign of rain — VELUX calls the VSS its greenest standard flat skylight. Roof pitch decides which mount is even eligible: deck-mounted fixed (FS), manual (VS), and electric (VSE) skylights are suitable for 14° - 85° roof pitch, while curb-mounted units are rated for 0° - 60°, with the curb-mounted manual VCM installable flat at 0°. The manufacturer's navigation also lists a self-flashed family — EVMS, EV, EF, and QPF — recorded here by name only. Every one of these is sold as a system: the skylight, its VELUX flashing kit matched to the roofing material, and optional shades, which is what the installation warranty is conditioned on.
Important Distinction
Note: A VELUX model code encodes mount type and operation, not size — sizes are separate codes (FS sizes run A06 through S06). Deck-mount and curb-mount versions of the same operation are different products with different pitch ranges: deck-mount fixed/venting units are rated 14°-85° while curb-mount units are rated 0°-60°. The self-flashed family (EVMS, EV, EF, QPF) is known here only from the manufacturer's product navigation; its individual product pages were not harvested, so no specs are asserted for it.
Also Known As
These are the search terms and phrases that commonly refer to this topic, so you can find it however you describe it.
How VELUX Skylight Systems and Model Codes Relates to Other Topics
The VELUX model-code roster makes the skylight-types discussion concrete: fixed vs venting and deck-mount vs curb-mount map directly onto FS/VS/VSE/VSS and FCM/VCM/VCE/VCS.
Understanding which VELUX system is on the roof — deck- or curb-mounted, fixed or venting — is the first step in diagnosing why an existing skylight leaks or planning its replacement at reroof time.
Roof pitch decides skylight eligibility: VELUX deck-mounted units are rated for 14°-85° roof pitch while curb-mounted units are rated 0°-60°, which is why low-slope roofs get curb-mount skylights.
Every VELUX Skylight System is warranted as a system: VELUX flashing is required to create the weathertight seal and to qualify for the 10-year installation warranty.
Reroofing is the natural moment to add or replace skylights, because the deck is exposed and the flashing kit integrates with the new roofing material rather than being retrofitted around it.
Deck-mounted skylights fasten directly to the roof deck, so the deck's condition around the opening matters before installation.
Roofing material selects the flashing kit: VELUX publishes tile-specific kits (EDW deck-mount, ECW curb-mount) whose patented sill flashing features pliable pleats that form to most types of tile.
Metal roofs take the EDM flashing kit, whose pieces interlock with the roofing material for a weathertight installation.
The solar-powered VSS and VCS systems are the models the old federal-tax-credit pitch attached to; the manufacturer's current 25(D) position is recorded separately.
Questions about VELUX Skylight Systems and Model Codes?
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