The new logo and identities were presented for the first time last night to advertisers and agencies at ITV’s headquarters on the South Bank in central London.
ITV plans to switch its five broadcast channels and on-demand service ITV Player to the new logos and identities on a single (to-be-confirmed) day in January.
Radcliffe said the scale of the changes will make it the "most ambitious" rebrand in the UK TV industry.
He said: "We’re going to flip the switch in January and it’s going to happen overnight. We have got a date in mind but with a project of this scale we’d be crazy to say it’s got to be that day."
From January, ITV’s main terrestrial channel will drop the '1' to return to the name ITV which Radcliffe called a "viewer driven decision" designed tol strengthen the affinity between the overall brand and the main channel.
Radcliffe said: "At the moment all of our viewers refer to ITV1 as ITV so we’ve always been swimming against the tide by calling ITV1 ITV1 so we’re just going to go back and be very simple.
"We want to create an ITV world with ITV at the heart of it and we’re going to drop this 1 because viewers have never embraced it."
The rebrand has been a year in the making and has been led by Radcliffe with Reemah Sakaan, director of network marketing, and Phil Lind, creative director of ITV’s in-house creative division ITV Creative.
On the main channel the new ITV logo will not have fixed colours but will use the theory of "colour picking" to take on the colours of the scenes being featured in each ident, allowing it to "flex according to the move and tone of the show".
As part of the changes ITV2 will be re-positioned as the home of "infectious entertainment from ITV", ITV3 will be home of "crafted drama collections" and ITV4 will be the "haven of sport and cult classics".
Sakaan said the ITV2 idents will paint the town "hot red", ITV3 will be a "luxurious cool midnight blue" and ITV4’s will be "cool slate grey" while the ITV Sport will be "turf green" and ITV News logo will be "dark blue".
Following Radcliffe’s arrival from Channel 4 last year ITV ended its relationship with Bartle Bogle Hegarty and brought its creative house. ITV now has a 50-strong in-house creative department.
Radcliffe said: "There’s something really nice about [the rebrand] being created from within the organisation.
"ITV has an amazing history, a great regional heritage but coming in here we did recognise that people love our shows but we don’t get the credit for the ITV brand that brings them to you.
"In this digital world, with hundreds of channels and hundreds of new media brands if you don’t elevate the brand which is bringing you these shows you are in an exposed position."
The last time ITV rebranded was in 2006 when it introduced the black and yellow colour scheme for ITV1 as part of a £3m investment.