Zone or Mullion Drained?
Zone Drainage

Zone drainage systems feature simple butt jointed mullions and transoms, with each panel acting as an individual unit.
Drainage and ventilation slots are located in the vertical pressure plate. Transoms are square cut at the ends to incorporate EPDM mouldings and gaskets to maintain each zone.
Transoms are fitted with a ‘Batman gasket’ to maintain the thermal performance.
Benefits
- Each panel is individually pressure equalised and drained via its transom, enabling the curtain wall to quickly react to fluctuating wind pressure
Mullion Drainage

Mullion (or point) drainage systems feature overlapping joints. Drainage and ventilation slots are located in the vertical pressure plate. Transoms are overlapped to the mullion which incorporates an EPDM gasket to seal between mullion and transom.
Transoms are fitted with a ‘Batman gasket’ to maintain the thermal performance.
Benefits
- Suitable for slope glazing