06/12/2026
In facade access, a mullion guide system is one of three primary methods of platform stabilization. As its name suggests, it involves the use of mullion guide tracks that are integrated into the building’s facade system. In a replacement project, the mullion track device (or mullion track shoe) is one of the most important elements of this system. Typically installed in pairs, these guide devices engage with the building’s mullion tracks at the start of the descent, providing a rigid and continuous restraint for the platform throughout any drop.
For this project, OTTE mounted the shoes on a horizontal track, which is mounted to the platform’s front facia, allowing them to be adjusted to span either 2 or 3 guide tracks. This in turn provides 2 operating configurations; one for window washing and the other for window replacement - adding flexibility without compromising safety.
In modernization projects, the challenge goes beyond simply replacing components. Years of service can introduce deformation and misalignment in the existing tracks, requiring a guide device that can still engage securely and travel smoothly along the façade.
Because in façade access, it’s often the details you don’t notice that matter most.
