Identify what deserves to stay
Photograph and record the stairs, doors, floors, openings and room proportions before demolition. Not everything must remain: identify what defines the home and what can change. A new opening or moved staircase calls for structural assessment first.
Fit services into the architecture
Ventilation, cooling, water and wiring affect ceilings and fitted furniture. Coordinate them with the layout before approving finishes. Include delivery routes for large pieces, working hours and community rules: an attractive design must also be buildable.
How to decide which original details to retain
Assess each feature for condition, architectural role and ease of adaptation. A well-proportioned door may be restored, but its geometry should be checked before ordering new joinery; an old floor may need work to its substrate. Discuss with the designer where an original detail can coexist with new services and where retaining it would create a lasting problem. Record these choices before demolition so they are not lost during construction.