For Velux® Windows

Your Velux® window should have a metal, plastic or sticker plate on the topside of the frame as you open the window. This plate or sticker contains codes, numbers and possibly a barcode. All you need to do is identify part ‘a’ and part ‘b’ as shown in the diagram to the right.

Code ‘a’ is a three letter code, such as GGL, GPU or VFB. Select this code in the ‘Window Type’ dropdown box.

Code ‘b’ is a string of letters and numbers, or numbers only, such as UK08 or 102. Select this code in the ‘Window Size’ dropdown box.

For Fakro® Windows

Your Fakro® window should have a metal, plastic or sticker plate on the topside of the frame as you open the window. This plate or sticker contains codes, numbers and possibly a barcode. You will be looking for the numbers in part 'B' of the diagram.

Code ‘B’ above, is what you need to focus on. It is a string of numbers, such as 78/98 or 55/78. Select this code in the ‘Window Size’ dropdown box - the codes on our site will match the size on your window.

For Keylite® Windows

Your Keylite® window should have a metal, plastic or sticker plate on the topside of the frame as you open the window. This plate or sticker contains codes, numbers and occasionally a barcode. All you need to do is identify the window size code. The window size code will either be a number or a number and a letter, for example 03 or 04G.

Make sure you take note of whether or not the number is followed by a letter, as these are different sizes. Window size 04A is different to 04, for example.

Simply select the relevant window size code in the dropdown box. *Please note 'T' Codes are new and can only be purchased directly from Keylite*

For Dakstra/Rooflite® Windows

Your Dakstra® or Rooflite® window should have a metal, plastic or sticker plate on the topside of the frame as you open the window. This plate or sticker contains codes, numbers and occasionally a barcode. All you need to do is identify the window size code.

The window size code will be a letter, followed by a number, followed by another letters, for example M4A.

Simply select the relevant window size code in the dropdown box.

Measuring the visible glass

Step 1: Measure the width of the visible glass to the edge of the beading to the nearest millimetre. Do not measure the beading. Take a note of this measurement.

Step 2: Measure the length of the visible glass to the edge of the beading to the nearest millimetre. Do not measure the beading. Take a note of this measurement.

Step 3: Using the tables below, find the skylight window code that matches your measurements.

Hint: If possible, try and determine the manufacturer of your skylight window, eg Velux®, to ensure we provide the best fitting solution for your skylight window.Can’t find a code that matches your measurement? No problem, start a live chat or give our team a call and we’ll find a solution for your ‘mysterious’ skylight window!