

The VELUX VS C04 Manual Fresh Air Skylight brings natural light and fresh air into your home. Designed for deck-mounted installation, it opens and closes manually with a smooth-turning handle for in-reach applications or a compatible control rod for out-of-reach installations.
Featuring Low-E glass, this skylight is a practical option for adding daylight and ventilation to living spaces, finished attics, and other rooms beneath sloped roofs.
The C04 model requires a rough opening of 21" wide x 37-7/8" high. VELUX offers additional glazing options for select configurations, including impact-resistant and snowload glass.
Features & Benefits
Product Specifications
| Specification | Detail |
|---|---|
| Brand | VELUX |
| Model | VS Manual Fresh Air Skylight |
| Size Code | C04 |
| Glass Type | Low-E |
| Operation | Manual |
| Mounting Type | Deck-Mounted |
| Rough Opening Width | 21 In. |
| Rough Opening Height | 37-7/8 In. |
| Roof Pitch Range | 14° to 85° |
| Ventilation | Opens for fresh air |
| Insect Screen | Included |
Frequently Asked Questions
What is the rough opening for the VELUX C04 skylight?
The required rough opening is 21" wide x 37-7/8" high. Always verify measurements against the current VELUX installation instructions before framing.
How does the VELUX VS skylight open?
The skylight opens and closes manually with a smooth-turning handle when within reach. A compatible control rod can be used for out-of-reach installations. Check whether the required operating accessory is included or sold separately.
What is Low-E glass?
Low-emissivity (Low-E) glass has a special coating designed to reduce heat transfer through the glazing while allowing natural light into the room.
Can I get this skylight with other glass options?
VELUX offers different glazing options for its skylight systems. Confirm availability and compatibility for the C04 size before ordering an impact-resistant, snowload, or other specialty glazing configuration.
Does the VELUX VS skylight provide ventilation?
Yes. The manually operated sash opens to allow fresh air into the room.
Installation Notes
Install according to VELUX's current instructions for the VS deck-mounted skylight. Confirm the rough opening, roof pitch, flashing system, glazing configuration, and compatibility with the roof assembly before installation.
Use the appropriate VELUX flashing system for the roofing material. Verify whether the operating handle or control rod is included with the selected product configuration.
| SKU | VSC04 | Brand | Velux |