Editing 10 Downing Street (section)

=== Rebuilding: 1960–1990 ===
[[File:President Ronald Reagan Meeting with Prime Minister Margaret Thatcher at 10 Downing Street in London, England.jpg|thumb|upright|Prime Minister [[Margaret Thatcher]] and U.S. President [[Ronald Reagan]] at 10 Downing Street in 1982.]]
By the middle of the 20th century, Number 10 was falling apart again. The deterioration had been obvious for some time. The number of people allowed in the upper floors was limited for fear the bearing walls would collapse. The staircase had sunk several inches; some steps were buckled and the balustrade was out of alignment. [[Dry rot]] was widespread throughout. The interior wood in the Cabinet Room's double columns was like sawdust. Skirting boards, doors, sills and other woodwork were riddled and weakened with disease. After reconstruction had begun, miners dug down into the foundations and found that the huge wooden beams supporting the house had decayed.{{sfn|Minney|1963|pp=428}}{{sfn|Jones|1985|pp=153–154}}

In 1958, a committee under the chairmanship of the [[David Lindsay, 28th Earl of Crawford|Earl of Crawford and Balcarres]] was appointed by [[Harold Macmillan]] to investigate the condition of the house and make recommendations. In the committee's report there was some discussion of tearing down the building and constructing an entirely new residence but because the prime minister's home had become an icon of British architecture like [[Windsor Castle]], Buckingham Palace and the Houses of Parliament, the committee recommended that Number 10 (and Numbers 11 and 12) should be rebuilt using as much of the original materials as possible.{{sfn|Minney|1963|pp=428}} The interior would be photographed, measured, disassembled, and restored. A new foundation with deep pilings would be laid and the original buildings reassembled on top of it, allowing for much needed expansion and modernisation. Any original materials that were beyond repair&nbsp;– such as the pair of double columns in the Cabinet Room&nbsp;– would be replicated in detail. This was a formidable undertaking: the three buildings contained over 200 rooms spread out over five floors.{{sfn|Seldon|1999|p=32}}

The architect [[Raymond Erith]] carried out the design for this painstaking work{{sfn|Minney|1963|pp=429–430}} and the contractor that undertook it was [[Mowlem|John Mowlem & Co]].<ref>{{cite news |url=https://www.telegraph.co.uk/news/obituaries/1351908/Sir-Edgar-Beck.html |archive-url=https://ghostarchive.org/archive/20220111/https://www.telegraph.co.uk/news/obituaries/1351908/Sir-Edgar-Beck.html |archive-date=11 January 2022 |url-access=subscription |url-status=live |title=Sir Edgar Beck |work=The Telegraph|date=9 August 2000 |access-date=5 June 2012 |location=London}}{{cbignore}}</ref>
''The Times'' reported initially that the cost for the project would be £400,000. After more careful studies were completed, it was concluded that the "total cost was likely to be £1,250,000" and the work would take two years to complete.<ref>The Times, ''Downing Street Reconstruction to Cost £1,250,000'', December 1959</ref> In the end, the cost was close to £3,000,000 and the work took almost three years due in large part to 14 labour strikes. There were also delays when archaeological excavations uncovered important artefacts dating from Roman, Saxon and medieval times.{{sfnm|Seldon|1999|1p=32|Jones|1985|2p=154}} Macmillan lived in [[Admiralty House, London|Admiralty House]] during the reconstruction.<ref>{{cite book|url=https://books.google.com/books?id=oGLGF9g_IIEC&pg=PA379|title=Supermac: The Life of Harold Macmillan|page=379|first=D. R.|last=Thorpe|year=2011|publisher=Pimlico|isbn=978-1844135417|access-date=18 March 2023|archive-date=26 March 2023|archive-url=https://web.archive.org/web/20230326164815/https://books.google.com/books?id=oGLGF9g_IIEC&pg=PA379|url-status=live}}</ref>

[[File:No 10 door installation (16242584649).jpg|thumb|left|The replica of the door with the [[Union Flag]] decoration in 2015]]
The new foundation was made of steel-reinforced concrete with pilings sunk {{convert|6|to|18|ft|m}}.{{sfn|Seldon|1999|p=33}} The "new" Number 10 consisted of about 60% new materials; the remaining 40% was either restored or replicas of originals. Many rooms and sections of the new building were reconstructed exactly as they were in the old Number 10. These included: the garden floor, the door and entrance foyer, the stairway, the hallway to the Cabinet Room, the Cabinet Room, the garden and terrace, the Small and Large State Rooms and the three reception rooms. The staircase, however, was rebuilt and simplified. Steel was hidden inside the columns in the Pillared Drawing Room to support the floor above. The upper floors were modernised and the third floor extended over Numbers 11 and 12 to allow more living space. As many as 40 coats of paint were stripped from the elaborate cornices in the main rooms revealing details unseen for almost 200 years in some cases.{{sfn|Seldon|1999|p=33}}

When builders examined the exterior façade, they discovered that the black colour visible even in photographs from the mid-19th century was misleading; the bricks were actually yellow. The black appearance was the product of two centuries of pollution. To preserve the 'traditional' look of recent times, the newly cleaned yellow bricks were painted black to resemble their well-known appearance.{{sfn|Jones|1985|pp=154–155}}{{sfn|Minney|1963|pp=429–433}}

Although the reconstruction was generally considered an architectural triumph, Erith was disappointed. He complained openly during and after the project that the government had altered his design to save money. "I am heart broken by the result," he said. "The whole project has been a frightful waste of money because it just has not been done properly. The [[Ministry of Works (United Kingdom)|Ministry of Works]] has insisted on economy after economy. I am bitterly disappointed with what has happened."{{sfn|Seldon|1999|p=34}} Erith described the numbers on the front, intended to be based on historical models, as 'a mess' and 'completely wrong' to a fellow historian.<ref name="Number Ten (Mosley)">{{cite web|last1=Mosley|first1=James|author-link=James Mosley|title=Number Ten|url=http://typefoundry.blogspot.co.uk/2010/10/number-ten.html|website=Typefoundry (blog)|access-date=14 July 2015|archive-date=15 July 2015|archive-url=https://web.archive.org/web/20150715054830/http://typefoundry.blogspot.co.uk/2010/10/number-ten.html|url-status=live}}</ref> 

Erith's concerns proved justified. Within a few years, dry rot was discovered, especially in the main rooms due to inadequate waterproofing and a broken water pipe. Extensive reconstruction again had to be undertaken in the late 1960s to resolve these problems.{{sfn|Seldon|1999|p=35}} Further extensive repairs and remodelling, commissioned by Margaret Thatcher, were completed in the 1980s under the direction of Erith's associate [[Quinlan Terry]].{{sfn|Seldon|1999|p=36}}