Transom in windows

A mullion is a profile rod dividing the window in vertical direction
Window wall


A transom corresponds to a profile rod that is horizontally placed in a window. A mullion is a profile rod dividing the window in vertical direction. There are different ways to connect transoms and mullions with the window frame or sash.

The most basic connection in PVC windows is done by V-notch cutting and pointed transom.
A V-notch heating element is used for this connection. This kind of transom connection is mainly applied in Great Britain, Ireland and the Netherlands. It allows welding of a Z-transom for outward-inward opening windows.

Next variant is screwing of transom profile in frame. For this version, the transom profile must be machined with a milling cutter on both sides according to the profile contour of frame.

A special heating element was developed for another visually attractive variant of transom connection in order to weld the inner profile walls with each other. Here again, the transom profile needs to be machined in advance on both sides in compliance with the profile contour.
Another possibility is based on a specifically designed transom-mullion connector to allow bonding between frame and sash.

We can also offer a solution for visually attractive butt-welding of Z-transom profiles for outward-inward opening windows.

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