What does FS/VS/VCM mean on VELUX skylights?

FS = Fixed deck-mounted; VS/VSE/VSS = Vented deck-mounted (manual/electric/solar). VCM/FCM are curb-mounted options, used most on low or flat roofs.

C06 is a standard VELUX size code. The letter maps to a width family and the number maps to height. Always verify rough opening on the official chart.

What does 2005 mean on the end of a VELUX part number?

It’s a bundle: 2 = white interior; 0 = aluminum cladding; 05 = Low-E3 glazing package (tempered/laminated varies by line).

Do I need a flashing kit?

Deck-mounted skylights typically use matched kits (EDL for shingles, EDM for metal). Curb-mounted units on flat roofs rely on the membrane-flashed curb itself.

Ordering VELUX Skylights

VELUX codes look cryptic, but once you know the pieces they’re simple. Below is the quick decode for mount type, venting, size codes (e.g., C06), and the finish/cladding/glass bundle (e.g., 2005). We also embedded the official VELUX size chart so you can cross-check dimensions.

TL;DR: FS = Fixed, deck-mounted. VS/VSE/VSS = Vented (manual/electric/solar), deck-mounted. CM/VCM/VCS = curb-mounted (build your own curb; best for low/flat roofs). C06 etc. = standard size codes. 2005 = interior 2 (white); cladding 0 (aluminum); glass 05 (Low-E3 tempered/laminated—varies by model).

Deck-Mounted vs Curb-Mounted

Deck-Mounted (FS/VS/VSE/VSS) fasten directly to the roof deck and use matched flashing kits with shingles or metal.

FS – Fixed (does not open)
VS – Vented (manual crank)
VSE – Vented (electric)
VSS – Vented (solar, remote)

Curb-Mounted (CM family: FCM/VCM/VCE/VCS) sit over a site-built curb. This is the go-to for flat or very low-slope roofs—you frame a curb (2x material), waterproof it (e.g., welded PVC/TPO with pre-formed corners), then set the skylight cap over it and fasten.

FCM – Fixed curb-mounted
VCM – Vented curb-mounted (manual)
VCE/VCS – Vented curb-mounted (electric/solar)

Decoding the Size (e.g., C06)

The letter maps to a width family; the number maps to a height. Common examples:

Code	Typical Rough Opening (approx.)	Notes
Axx	~14½" width	Great for tight rafter spacing
Cxx	~21" width	E.g., C06 very common
Mxx	~30" width	Larger daylight opening
Sxx	~44" width	Big, dramatic light

Use the official chart below to confirm exact rough openings and glass sizes for your specific model.

What “2005” Means (Finish / Cladding / Glass)

Digit(s)	Meaning	Common Choice
2xxx	Interior finish	2 = White (factory white interior)
x0xx	Exterior cladding	0 = Aluminum cladding (Cool Grey)
xx05	Glazing	05 = Low-E3 tempered/laminated package (varies by line)

Flashing Kits (Don’t Skip These)

EDL – Shingle flashing kit (deck-mount)
EDM – Metal roof flashing (standing seam/AG panels; deck-mount)
ECL – Curb-mount flashing for shingles
Tile options – EDW/ECW, and multi-unit kits EKL/EKW

Flat/low-slope curb-mount installs typically don’t use a separate “kit”—the curb itself is flashed and waterproofed with your membrane (PVC/TPO/EPDM) and the skylight cap sheds over it.

VELUX Size Chart (Embedded)

If you don’t see the tool load below, open it directly: VELUX Product Sizes. Heads-up: your site must allow frame-src https://www.veluxusa.com in the Content-Security-Policy.

Quick Examples

FS C06 2005 — Fixed, deck-mounted; size C06; white interior, aluminum cladding, Low-E3 glass.
VCM 1446 2005 — Vented, curb-mounted; outside-curb size ~14x46 family; white interior, aluminum cladding, Low-E3 glass.

Installing and cleaning a velux skylight auburn al — Installing and cleaning a Velux skylight in Auburn AL

Small square skylight over bathroom auburn al — Small square skylight over a bathroom in Auburn

Velux skylight installed on shingle roof auburn — Velux skylight installed on a shingle roof

A finished velux skylight in bathroom install cary woods auburn al — Skylights can add lots of light to bathrooms or other darkly-lit rooms

Solar tubes are a cheaper alternative to let light in auburn opelika al — Solar tubes are a cheaper alternative to let light in (Opelika)

Solar tube installed from shingle roof auburn opelika al — Solar tube installed on roof (Opelika/Auburn area)

Need help picking the right unit and flashing? Call/text 334-332-7799. We’ll confirm roof slope, deck condition, venting, and bring samples.