Stiff sash lock on a 1950s–60s new-town semi-detached
Common on 1950s–60s new-town semi-detached across Cwmbran — the timber door has moved seasonally and the mortice case has bound against the keep. We often see this coupled with aged lever-tumbler locks on 1950s new-town semi-detached doors with non-standard backsets. The fix is either service (lubricate and adjust) or replace with a BS3621 equivalent if the existing lock is pre-standard.
Our approach Service first if the mechanism is sound; BS3621 upgrade if the existing lock is sub-standard or worn beyond service.