Offset Asymmetrical Cylinders for Thermal Break Aluminum Facades
Engineering Overview: Technical guide on calculating and specifying offset asymmetrical Euro profile cylinders for insulated thermal break aluminum entrance facades.
Technical & Engineering Specifications
| Standard | DIN 18252 / EN 1303 |
|---|---|
| Backset Range | 25 mm, 30 mm, 35 mm Narrow Stile |
| Body Material | Solid Extruded H59 Brass |
| Asymmetric Splits | 30/40, 30/45, 32.5/37.5, 35/45, 30/50 mm |
| Profile Application | Thermal Break Aluminum & Curtain Wall Doors |
Thermal Break Profile Geometry
Modern commercial aluminum doors incorporate internal polyamide insulating struts (thermal breaks) and deep structural glazing channels. This cross-sectional geometry shifts the mortise lockcase pocket away from the door leaf centerline toward the interior.
Asymmetrical Split Specifications
Standard symmetrical cylinders (e.g. 35/35 mm) will sit unevenly. Installers must specify Offset Asymmetrical Cylinders:
- Common Splits: 30/40 mm, 30/45 mm, 32.5/37.5 mm, 35/45 mm.
- Datum Point: All offset measurements are calculated from the central M5 retaining screw centerline to the interior (Dim A) and exterior (Dim B) finished escutcheon faces.
Frequently Asked Engineering & Selection Questions
Q1: Why cannot symmetrical cylinders be used on thermal break doors?
Thermal break struts position the lockcase off-center, causing symmetrical cylinders to stick out too far on one side and sit sub-flush on the other.