Window performance on this draught-reduction windows installation in Kirkdale depends on more than the frame profile. We start with keeps and adjust keeps to achieve consistent engagement without making operation unnecessarily stiff. sash compression is then coordinated through frame fit, gaskets, locking compression, perimeter seals and reveal condition, so we set sash compression evenly enough to support sealing without creating heavy operation, with keeps kept as the lead check for this draught-reduction windows scope. Before final finishing, we review frame dimensions and confirm manufacturing dimensions against the surveyed opening before the replacement frame is ordered, with keeps kept as the lead check for this draught-reduction windows scope. We finish with packers and support the frame at suitable points so fixing does not pull it out of line, supporting a tighter window installation with frame and sash sealing checked together, with keeps kept as the lead check for this draught-reduction windows scope.