Readhead was born in 1819 and was a millwright at Earsdon Colliery. He then pursued the same job at Marshall's shipyard between 1842 and 1858. He was appointed manager at Marshall's new yard at Willington Quay but left 6 years later to set up a yard with Softley at the Lawe.

Their partnership ended in 1872 and John likely continued at the Lawe. Readhead produced iron steamers from the outset for the cargo trade, rarely stepping away from what provided him a solid reputation.

It fast outgrew the capacity he had here, so by 1880 he moved to a new site at West Docks where his legacy has remained. The new yard was much bigger, with 1000ft of frontage and space for three berths though this was increased to four. The yard can be seen on the 1890s map in great detail, covering a huge parcel of land with Readhead's original graving dock and 3 others, as well as a larger yard with an internal tramway system, engine house and weighing machine.

Readhead continued building his reputation with tugs and small iron engines, though did continue to expand with in-house engine and boiler manufactories. John's whole family were part of the business so changed to & Sons in 1888. Readhead established links with various merchants, most notably Edward Hain who placed 87 orders. Readhead diversified in later years producing ships for the Ministry of War during the war as well as bulk carriers for international merchants. Readhead's maintained a solid ship repair business through the depression of the 20s and orders totally dried up in the inter war period. This was restarted in WWII despite significant damage due to German bombings. Tyneside was a priority target due to the sheer extent of industry on the river. Orders did continue through to the 60s when the yard was absorbed by Swan Hunter, who maintained existing contracts.

The last ship built at South Shields was Singularity in 1977, for FT Everard & Sons Ltd.