The 30-second version
- Step 1: Roof pitch first. Flat / low-slope (0–15°) → curb-mounted (FCM / VCS / VCM). Pitched (15°+) → deck-mounted (FS / VS / VSE / VSS).
- Step 2: Fixed or venting? Living rooms and bedrooms → fixed is fine. Kitchens and bathrooms → venting (VS manual / VSE electric / VSS solar-powered).
- Step 3: If venting, which motor? Wiring already there → VSE. No wiring → VSS solar (most popular). Manual and cheap → VS.
- Step 4: Size. Small room → C-series (21" wide). Standard bedroom → M-series (30" wide). Great room → S-series (44" wide) or FCM up to 4' × 6'.
- Skip Sun Tunnels for now — those are for windowless interior rooms (hallways, closets), a different product entirely.
Why this decision is harder than it should be
Velux has been the dominant residential skylight brand in North America for 50+ years. Their catalog is massive: fixed and venting, deck-mounted and curb-mounted, manual and electric and solar-powered, six glazing options, five size categories, four remote-control systems, and hundreds of shade combinations. The 2026 residential catalog runs 28 pages.
Contractors typically default to whatever they've installed most recently. That's fine if you have a standard installation, but it costs you money and functionality if your home actually needs something different. This guide walks through the four decisions that matter, in order of impact.
Decision 1: Roof pitch determines installation type
Every Velux skylight is either deck-mounted or curb-mounted. This is the first fork in the decision tree and it's dictated by your roof, not your preferences.
Deck-mounted (VS / VSE / VSS / FS)
The skylight attaches directly to the roof deck (plywood or OSB) below your shingles or tile. Installation is flush — the skylight sits low against the roof plane. Requires roof pitch 14° to 85° (3:12 to 137:12) — most residential pitched roofs.
You want deck-mounted if: your roof has a visible pitch, you're doing new construction or a full re-roof, and you want the cleanest exterior appearance.
Curb-mounted (VCS / VCE / VCM / FCM)
The skylight sits on a wooden curb — a small rectangular frame built on the roof around the opening, raised 4"–6" above the roof plane. Works on pitches from 0° to 60°.
You want curb-mounted if: your roof is flat or low-slope (typical of mid-century modern homes in Cal Heights, Silver Lake, Culver City, and Pacific Palisades pre-fire stock), or you're replacing an old dome skylight that was already curb-mounted (existing curb can often be reused).
The FCM Fixed Curb-Mounted is the single most-installed Velux skylight in Los Angeles because so much of LA's mid-century architecture has flat roofs.
Decision 2: Fixed or venting?
Once you know installation type, you pick between fixed (glass doesn't open) and venting (glass tilts open 8°–10° for airflow).
Fixed (FS deck-mounted / FCM curb-mounted)
Cheaper, simpler, no motor to maintain, no shade required. Right choice for living rooms, dining rooms, bedrooms, hallways, and any space where you don't need to actively vent heat or moisture.
Venting (VS / VSE / VSS deck-mounted; VCM / VCE / VCS curb-mounted)
Adds a motor and hinge so the sash opens. Critical for:
- Kitchens — evacuates cooking heat and moisture more effectively than a range hood alone
- Bathrooms — flushes shower steam, prevents mold on ceilings
- High-heat rooms — south-facing spaces that build up 15°+ above outdoor temperature during summer, especially in Reseda, Highland Park, Culver City interior rooms
- Bedrooms in older homes without AC — passive night-cooling via chimney effect
Decision 3: If venting, choose your motor
Three flavors of venting skylight, differing only in how the sash opens.
VS — Manual (cheapest)
Hand-operated via handle within reach, or a telescoping control rod up to 15' for higher ceilings. No electrical, no rain sensor. Right choice if the skylight is genuinely within arm's reach and budget is tight.
VSE — Electric (best if wiring is already there)
Concealed motor, factory-paired remote control, built-in rain sensor auto-closes on precipitation. Requires 110V wiring pulled to the skylight location. If wiring exists nearby (attic-mounted junction box, for example), VSE is straightforward. If wiring needs to be pulled fresh, add $400–$1,200 to project cost — often enough to make VSS the better economic choice.
VSS — Solar-Powered (most popular in LA, no wiring needed)
Discreet solar panel on the skylight exterior charges an internal battery. Same features as VSE (motor, rain sensor, remote) but zero electrical work required. Also qualifies for the federal 30% Residential Clean Energy Credit in the tax year of installation — the skylight + shade system itself, not just the panel.
For 80%+ of LA retrofits where electrical isn't already run to the skylight location, VSS is the correct choice. It costs slightly more at material level but saves the electrician trip and drywall patching.
Decision 4: Sizing
Velux uses two-letter size codes on deck-mounted units. The first letter is width, second letter + number is height. Common sizes:
- A06 (14.5"×46"): narrowest — for tight spaces
- C-series (21" wide): hallways, small bathrooms, closets
- D-series (22.5" wide): designed to fit between 24" o.c. roof trusses — new construction favorite
- M-series (30" wide) — most popular for bedrooms, kitchens, standard rooms
- S-series (44" wide): great rooms, vaulted living rooms
Curb-mounted (FCM) uses inch-dimension codes. Common sizes: 2222 (25.5"×25.5"), 2246 (25.5"×49.5"), 3046 (33.5"×49.5"), 4646 (49.5"×49.5"), 4672 (49.5"×75", largest standard). Custom sizes are available for FCM only, up to 10 feet on the longest dimension.
Sizing rule of thumb: total skylight square footage should be about 5–10% of the room's floor area. A 200 sqft bedroom wants 10–20 sqft of skylight — one large or two mediums. Under-sizing leaves the room feeling dim; over-sizing overheats it in LA summers.
What Sun Tunnels do (and don't) solve
Sun Tunnels are Velux's small-diameter reflective tube skylights (11", 15", or 22" ceiling opening) that carry daylight from a roof-mounted collector down through a reflective tube to a diffuser flush with your ceiling.
Right use case: windowless interior rooms — hallways, walk-in closets, laundry rooms, powder rooms, small bathrooms with no exterior wall. Sun Tunnels install in under a day, cost $1,000–$2,200, and fit between existing ceiling joists (no framing modification).
Wrong use case: replacing a real skylight or lighting a full room. Sun Tunnels deliver roughly the light output of a 100W bulb — enough to illuminate a small space, not enough to compete with a proper skylight for a bedroom or living area.
Full breakdown: Velux Sun Tunnel Skylights Guide.
Glazing upgrades worth considering
All Velux skylights ship standard with double-pane, argon-filled, laminated safety glass with LowE³ coating — appropriate for LA in most cases. Optional upgrades:
- Impact Glass: hurricane-rated laminated. Add for coastal exposure (Malibu bluffs, Manhattan Beach oceanfront, Marina Del Rey waterfront) where wind-driven debris is a real concern.
- White Laminated Glass: internal interlayer diffuses direct sunlight, reduces glare on TVs and computer monitors below.
- Triple-Pane (FCM only): maximum thermal performance. Meaningful in Reseda / Valley heat, less so at the coast. Note: precludes the solar shade upgrade.
Shades and remote controls
The Velux Skylight System bundles the skylight + solar-powered shade + factory-paired remote. Shade options range from light-filtering to full blackout, and colors span 40+ options.
All powered skylights (VSE / VSS / VCE / VCS) integrate with the Velux App Control and Velux ACTIVE smart-home systems for scheduling, HomeKit / Google Assistant voice control, and automatic climate-based venting.
Common LA scenarios — quick recommendations
- Mid-century modern flat-roof living room (Silver Lake, Culver City): FCM 4646 or 4672, fixed, standard glass — $3,400–$8,500 installed
- Master bedroom on pitched roof, needs venting: VSS M06 with room-darkening solar shade — $3,200–$5,800 installed
- Interior bathroom, no exterior wall: Sun Tunnel TGR 014 rigid — $1,000–$2,200 installed
- Kitchen skylight, high ceiling: VSE M08 with rain sensor — $3,000–$5,200 installed (add electrician cost if wiring not present)
- Attic conversion or ADU with pitched ceiling: GGU MK06 or MK08 roof window — $2,200–$4,500 installed
- Palisades or Malibu rebuild — architect-designed great room: Custom GSM SkyMax up to 4' × 8' — $7,500–$14,000 installed
Get a Velux estimate for your LA home
Halo Build Co is a Velux dealer serving all of Greater Los Angeles. We spec the right unit during a free on-site consultation — factoring in roof structure, sun exposure, ceiling type, and code compliance (Chapter 7A if you're in a fire zone). Written estimate the same week.