Alastair David Simms was born in 1963 and grew up in the market town of Masham in North Yorkshire. He attended Masham CofE Primary School from 1968 to 1974 and Bedale High School from 1974 to 1979.

His career in coopering began by accident, destined by his father to become a bricklayer, Alastair took a holiday job at the local Theakston Brewery in Masham and was asked to assist the cooper. Watching the craft, he was immediately captivated and began his apprenticeship four days after his 16th birthday.

He became a journeyman cooper in 1983 and attained the rank of master in 1994 when his own apprentice completed training, the traditional requirement for mastery.

After leaving Theakston Brewery in 1995, he worked for eighteen years at Wadworth Brewery in Devizes. In 2013 he set up his own business, White Rose Cooperage Ltd, based in Yorkshire. The company was backed by Yorkshire Bank and aimed for a £100,000 turnover in its first year of trading.

Simms has appeared as an expert on the BBC television series The Repair Shop. He also served as a part-time firefighter with North Yorkshire Fire and Rescue Service from September 1981 to March 1995, alongside his coopering career.