For extension uPVC windows in Knutsford, the technical sequence begins with glass specification, so we match glazing type and pane configuration to the intended room use and project specification, with glass specification kept as the lead check for this extension windows scope. We then use external making good to coordinate prepared openings, lintels, cavity closures, sill levels and external finishes, and we finish external reveals, render or masonry interfaces around the installed frame, with glass specification kept as the lead check for this extension windows scope. Before closure, frame position is reviewed and we set the new frame at a position that works with the reveals, sill and external finish, with glass specification kept as the lead check for this extension windows scope. The handover also covers cavity closure; we check the window perimeter where the opening meets cavity closers or insulated reveal construction, with glass specification kept as the lead check for this extension windows scope. Together these checks support window installation aligned with the wider extension build and finish sequence.