VELUX Product Codes Explained & Where To Find Them

VELUX products are identified with a three part code, designed to quickly and easily show the different elements of each product. Once you know what each part means, it's easy to find the exact product you need. Here, we break down the different elements of the code used for VELUX windows and flashing.

VELUX Window Codes

The three different elements of a VELUX window code show what type of window it is, the interior finish, the size, the glazing and the control mode.


  • G - the first G simply indicates the product is a window
  • G or P - the second letter indicates whether the window is centre pivot or top hung
  • L or U - the third letter is used to show whether it is white painted or pine (L), or white polyurethane (U)

Width & Height

There are various widths and heights available for VELUX windows, with some more common in buildings than others. Some of those common sizes are as follows:

  • Width:
    • CK = 550mm
    • FK = 660mm
    • MK = 780mm
    • PK = 942mm
    • SK = 1140mm
    • UK = 1340mm
  • Height:
    • 01 = 698mm
    • 02 = 778mm
    • 04 = 978mm
    • 06 = 1178mm
    • 08 = 1398mm
    • 10 = 1600mm

Note: Pre-2014 windows will not have a 'K' in the code.

Finish & Glazing

The last part of a VELUX window code has several different elements, signifying various different aspects of the finished product.

  • The internal finish - 0 (white polyurethane), 2 (white painted) or 3 (clear lacquer)
  • The external finish - 0 (standard grey), 5 (black, only for conservation windows) or 8 (special colour)
  • The pane variant - 70 (double glazed), 66 (triple glazed), 67 (triple glazed), 68 (triple glazed), 69 (triple glazed), 62 (triple, extra noise reduction)
  • Add-ons - 21U (electric), 30R (solar), 40 (smoke vent), H (glazing bar), Q (enhanced security), R (rain noise reduction)

VELUX Flashing Codes

As with VELUX windows, there are three elements to the codes used for VELUX flashing. The middle section of the code uses the same format for size as the windows (see above), so the same size flashing will be used as for your window.


  • E - the first E simply indicates the product is a flashing
  • Flashing style - D (single flashing), B (twin), K (combi), F (sloping / vertical)
  • Roofing material:
    • Standard installation height (red line): L (slate), W (tile), P (plain tile)
    • Recessed installation height (blue line): N (slate), J (tile)

Width & Height

As mentioned above, the width and height codes (e.g. CK04) for VELUX flashings are the same used for the roof windows, making it easy to determine which one is required.

Gutter, Finish, Element No. & Frame Gap

The last part of a VELUX flashing code breaks down into four different sections, which refer to aspects such as the gutter, external finish and frame gap. There are a variety of combinations available, and the Roof Giant sales team can provide any assistance you require.

Where To Find Your VELUX Code

Your VELUX window will have a plate in the top corner of the frame, visible when open, which provides the information you'll need in the form of the three-part code we outlined above.

This will make it easy to replace an existing window, but can also be used to order spare parts, new glazing or even blinds. When you're replacing a window, it is easiest if the size remains the same (although the size can be increased if your project requires it), and other aspects can be changed to suit your new requirements (e.g. new opening, or a new finish).

Where To Find Your VELUX Code