The new thermal split mullion brings commercial flushglaze detailing to the APL Architectural Series ThermalHeart+ 114mm range, extending design options across both commercial and residential projects.

The split mullion simplifies the installation of long, straight runs of pre-built modular panels, with built-in tolerance for building movement and thermal expansion. The movement range can be set to suit project requirements.

It is compatible with all seismic frames and sill tray solutions in the 114mm range. A 44 × 19mm glazing rebate accommodates double-glazing options up to 32mm thick.

The release also marks the first step in APL’s thermal Commercial Series rollout. A seismic transom is planned for release in 2027, extending the system into a full thermally efficient unitised façade solution.