On this cottage-style windows project in Gainsborough, perimeter sealing is the first installation control and we form a continuous weather-resistant seal around the external frame perimeter, with perimeter sealing kept as the lead check for this cottage-style windows scope. Kaizen Windows & Doors links gaskets to mullion positions, opening lights, glazing bars, frame proportions and hardware, making sure we check glazing and sash seals for continuous seating before final handover, with perimeter sealing kept as the lead check for this cottage-style windows scope. We also review final checks before making good and open, close, lock and inspect each installed window before the work is handed over, with perimeter sealing kept as the lead check for this cottage-style windows scope. Finally, sill level is checked so we can coordinate the frame base with the internal sill or window board and the external weathering detail, helping deliver a more traditional visual arrangement delivered through a low-maintenance uPVC window system, with perimeter sealing kept as the lead check for this cottage-style windows scope.