led to an overhaul of the British weights and measures system. An inquiry that ran from 1838 to 1841 considered the two competing systems used in the country, the avoirdupois and troy measures, and decided that avoirdupois would be used forthwith; troy weights were retained solely for gold, silver and precious stones. The destroyed weights and measures were recast by William Simms, the scientific instrument maker, who produced the replacements after "countless hours of tests and experiments to determine the best metal, the best shape of bar, and the corrections for temperature". The Palace of Westminster has been a UNESCO World Heritage Site since 1987, and is classified as being of outstanding universal value. UNESCO describe the site as being "of great historic and symbolic significance", in part because it is "one of the most significant monuments of neo-Gothic architecture, as an outstanding, coherent and complete example of neo-Gothic style". The decision to use the Gothic design for the palace set the national style, even for secular buildings. In 2015 the chairman of the House of Commons Commission, John Thurso, stated that the palace was in a "dire condition". The Speaker of the House of Commons, John Bercow, agreed and said that the building was in need of extensive repairs. He reported that parliament "suffers from flooding, contains a great deal of asbestos and has fire safety issues", which would cost £3 billion to fix. Notes and references Notes References Sources 1834 fires in Europe 1834 in London Fires at legislative buildings Palace of Westminster Political history of London Building and structure fires in London October 1834 events 1834 disasters in the United Kingdom Burned buildings and structures in the United Kingdom