For whole-house window replacement in Preesall, the technical sequence begins with opening survey, so we check the existing opening, frame position and surrounding finishes before final dimensions are confirmed, with opening survey kept as the lead check for this whole-house replacement scope. We then use cill projection to coordinate multiple openings, room use, frame styles, access and making-good interfaces, and we set the cill projection and end details to suit the opening and surrounding finish, with opening survey kept as the lead check for this whole-house replacement scope. Before closure, perimeter sealing is reviewed and we form a continuous weather-resistant seal around the external frame perimeter, with opening survey kept as the lead check for this whole-house replacement scope. The handover also covers trickle vents; we integrate background ventilators with the frame head, room use and internal finish where specified, with opening survey kept as the lead check for this whole-house replacement scope. Together these checks support a consistent window package with installation details coordinated across several rooms.