GT55 TB Commercial Door




With security front-of-mind, the GT55 TB is one of the most comprehensive aluminium door systems on the market.  The systems boast PAS 24 rating and Secured by Design [SBD] accreditation across a suite of configurations including; single and double doors, screening, side and fan lights.  As well as featuring impressive panic, mechanical and electro-mechanical locking for both single and double doors.  

The GT55 TB system is ideal for a range of heavy duty commercial and public sector applications including offices, hospitals, schools and multi-residential buildings.

The GT55 TB offers exceptional performance, achieving remarkably low U-values of 1.7 Uw with double glazing and 1.5 Uw with triple glazing.

GT55 TB Data sheet

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Design features

  • Security tested to PAS 24
  • Thermally broken for enhanced performance
  • Sightlines of 145mm (single door) and 176mm (double door)
  • Anti-finger trap styles
  • Mid-rail and lay bar
  • Angular corner feature designs


  • Single and double door configurations
  • Available with a full range of security and customisable hardware
  • Mechanical and electro-mechanical multipoint locking options
  • Electronic and manual access systems easily integrated
  • Glazed or non-glazed options
  • Available in single or dual colour option, polyester powder coating and anodised finishes
  • Standard or DDA compliant overhead closer
  GT55 TB Single GT55 TB double
U value W/m²K (Double glazing) : 1.9 W/m²k 1.82 W/m²K
U value W/m²K (Triple glazing) : 1.72 W/m²K 1.62 W/m²K
Acoustic performance (dB) : npd npd
Air tightness (Pa) : Class 0 (0 Pa) Class 0 (0 Pa)
Water tightness (Pa) : Class 1A (0 Pa) Class 1A (0 Pa)
Wind load (Pa) : Class 0 (0 Pa) Class 0 (0 Pa)
Security : Q-mark Q-mark
Certifications : Q-mark Q-mark
Durability EN1191 category : 50,000 Cycles 50,000 Cycles
Size limits
System depth : 110 mm 110 mm
Maximum door leaf size : 1250mm x 2400mm 2500mm x 2400mm
Maximum door leaf weight : 110kg 110kg
Glazing thickness : 24mm - 40mm 24mm - 40mm
Thermally broken : X X
Low threshold : X X
Panel door : X X
Multi-point locking : X X
Barrel hinges : - -