Westminster Hall, the oldest part of the Palace of Westminster, has undergone a decade-long conservation project led by Donald Insall Associates, ensuring its preservation for future generations. Constructed in 1097, this Grade I-listed hall has been central to British history, hosting significant events such as coronations, state trials, and the Queen's lying-in-state. The comprehensive conservation effort, spanning from 2010 to 2020, addressed various aspects of the hall's structure and aesthetics.

Throughout the restoration, the hall remained accessible to the public, underscoring its role as a living monument of democracy. The project not only preserved the hall's structural integrity but also contributed to the advancement of conservation techniques, influencing the preservation of historic structures across the UK.
In recognition of this monumental effort, the conservation of Westminster Hall was honored with the Europa Nostra Award in 2024, celebrating excellence in cultural heritage preservation.