Looking at the latest proposals for the restoration of the Houses of Parliament, there is one detail that jumps off the page. Much has been said about the urgent need to modernise the building, but it is the extraordinary length of the programme of works proposed – up to 61 years for the longest recommended option – that has caught the attention of the industry.

How can the refurbishment of one building –albeit a very large, grade I-listed building – take more than six decades to complete? The timescale is only 15 years off the time which has elapsed since the last renovation, completed in 1950, implying that, by the time the works are finished, the first parts of the job to complete would be almost ready for restoration again.

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