Gibb was born in Broughty Ferry, Dundee, the son of the civil engineer, Alexander Easton Gibb, and the great-grandson of John Gibb, an early member of the Institution of Civil Engineers. He was educated at the High School of Dundee, Rugby and University College, London, although he left the latter after a year to become articled to the prominent Civil Engineers John Wolfe-Barry and Henry Marc Brunel. Having completed his training, he became resident engineer on the Metropolitan District Railway's Whitechapel and Bow Railway extension (with Charles Inglis (engineer)). After two years he left to join his father's company, Easton, Gibb & Son, of which he later became managing director.
In 1916, Gibb was appointed Chief Engineer Ports Construction to the British Army in France, with the rank of Brigadier-General. In 1918 he became Civil Engineer-in-Chief to the Admiralty and the Admiralty M-N Scheme, was one of his major projects. Then in 1919, he became Director-General of Civil Engineering with the new Ministry of Transport.
In 1921 he left government service and became a consulting engineer, founding Sir Alexander Gibb & Partners in the following year. This grew to become the largest civil engineering consultancy in the United Kingdom and was involved in large-scale projects all over the world.
Gibb was appointed Companion of the Order of the Bath (CB) in 1918 for his war work and was knighted later the same year as Knight Commander of the Order of the British Empire (KBE). He was promoted to Knight Grand Cross (GBE) in the 1920 civilian war honours.
He also wrote The Story of Telford: The Rise of Civil Engineering, a biography of the Civil Engineer Thomas Telford, to whom his great-grandfather John Gibb had been a deputy. In 1936 he became President of the Institution of Civil Engineers and in the same year he was elected a Fellow of the Royal Society.
- Godfrey Harrison (First published in 1950). Alexander Gibb – The Story of an Engineer, Geoffrey Bles, London.
- Biography, Oxford Dictionary of National Biography
- Sir Alexander Gibb at the Biographical Database of the British Chemical Community, 1880–1970
|Professional and academic associations|
John Duncan Watson
|President of the Institution of Civil Engineers
November 1936 – November 1937