The twists and turns of making a secondary glazing arch

From conception to installation, every step of a secondary glazing project must fit.  The glass must fit into the sashes, the sashes need to fit within the frames. The frames must fit their respective timber ground’s, which in turn needs to fit snuggly into its particular opening. All these steps need to work together whilst the whole secondary glazing treatment should blend in seamlessly with the overall project; retrofit or refurbishment. Being a ‘finishing product/trade’, secondary glazing requires no additional adaptation or decoration work after installation, so ideally this should be scheduled for installation when all the reveals have been decorated and ‘made-good’.   Creating a curved aluminium frame Curved secondary glazing projects involve additional steps in the process; the mapping of the window openings and the production of CAD (computer-aided design) drawings and templates.  At survey the curved window opening is mapped precisely with a 3D laser template and a DXF file created. The CAD team take the DXF of the opening and create a full scaled drawing of the treatment. These are used to create 1:1 tracings for use in the manufacturing process. The templates communicate the exact curve, the spring point, the position and angle of joints as well as setting out information for rolling, cutting and production of the timber grounds or sub frames. For each curved secondary glazing unit templates are produced for the three sections: Glass procurement: It is vital that the supply chain is as informed as our own production team for the final assembly to work. Frame and sash production: This specialist section is responsible for curving aluminium to create both the frame together with the vent or insulating sash components of the secondary glazing. Timber: The timber shop creates the timber ground which will be installed into the reveal. This forms the base into which the secondary glazing is subsequently fixed. Face fixed secondary glazing requires an additional (often decorative) frame which sits in front of the original reveal. CAD Drawing for Arch - Calibrations on Roller Machine The curving experts within the factory are adept at translating the CAD drawing and template into the setting needed to create the exact curvature with the ‘Ring Rolling’ machine.