Coronation Street chiefs have announced plans to extend the set of the long-running ITV soap.

The extension will include a new exterior build called the Weatherfield Precinct as plans are unveiled on the week the most-watched soap in the UK has moved to new hour-long episodes in a new 8pm slot.

The show’s set, a 7.7 acre site in Trafford near Manchester, will be extended to make way for a two-storey construction featuring maisonettes, a staircase and balcony leading to the properties, a piazza and an array of accessible local shops and units.

Construction on the new development begins this week and is expected to take six months to complete.

Coronation Street’s production designer, Rosie Mullins-Hoyle, said: “We are extremely excited to be starting to build Weatherfield Precinct this week after a year of technical drawings, model making, visualising and planning.

“An incredible amount of research has been carried out focusing on 1960s local architecture and we are striving to create an authentic area of Weatherfield with a grittier vibe to the existing street that we know and love.”

ITV writers will have opportunity to broaden Coronation Street

The precinct is not an entirely new concept having previously been referenced in the soap’s dialogue with characters heading off to the parade of shops.

However, the new set will afford scriptwriters the chance to broaden the show, creating opportunities to explore storylines beyond the cobbles of Coronation Street itself, ITV said.

Coronation Street’s series producer, Iain MacLeod, said: “The fabled Weatherfield Precinct has been much discussed, but little seen on the show in our 61 years, and I am really excited to be expanding the Coronation Street universe.

“The plans for the shopping area are drawn directly from the real-world Salford environs that inspired the show’s creator Tony Warren and exemplify the authenticity and ambition we still prize as we move to hour-long episodes this week.”

Coronation Street is the world’s longest running TV soap and holds the Guinness Book of World Records for this achievement, alongside longest serving cast member, William Roache OBE, who has starred in the drama serial as Ken Barlow since the first episode on 9 December 1960.