Buckingham Palace is to undergo a £369m M&E refurb over the next decade.
Funding has been agreed for the 10-year programme to overhaul the palace’s plumbing, electrical, cabling and heating systems.
The current systems were installed after the Second World War and officials fear that the ageing facilities could fail and cause significant fire and flooding damage.
Work will start in April 2017 and be divided into multiple phases, with contracts being awarded separately for each phase of work.
The high-priority works phase will start first, with the palace’s electrical and heating generation and distribution facilities replaced over the first two years.
From April 2019, work will progress through the east wing and rotating clockwise through the south, south-west and north wings.
The west wing and state departments will be progressed incrementally – two to three rooms at a time - to allow people to continue to visit the palace.
Work will be funded through an increase in the sovereign grant from 15 per cent to 25 per cent of the Crown Estate’s profits over the next ten years.
Chief secretary to the treasury David Gauke said: “We must ensure that the special architectural and historic nature of some of our greatest buildings are protected for future generations, therefore it is only right we ensure Buckingham Palace is fit for purpose.
“These urgent works have been properly costed and will ensure the palace can continue its centuries-long tradition of being the working house of our monarch.
“We will ensure every penny spent achieves the greatest value for money.”