The BBC’s attempt to build a new Albert Square for the filming of EastEnders has been heavily criticised by a group of MPs, who have questioned whether the enormous £87m cost of the project ain’t worth it.

The project to build an entire new stage set for the flagship soap opera is now running £27m over budget and is not due to be completed until May 2023, nearly five years later than originally planned. The new set is part of a wider programme called “E20” that also includes new production facilities.

Among other issues, the MPs said the BBC had failed to take into account how to age the new brick buildings to ensure they do not look different on screen to the rickety mid-1980s facades that have served EastEnders for the last 35 years.

The corporation had initially hoped to carry out the ageing process while constructing new versions of recognisable buildings such as the Queen Vic pub. However, it was later decided this was too complicated and the BBC will instead spend £3.5m making the sets looking authentically old, in a process that could take up to 13 months.

The House of Commons public accounts committee report, which follows last year’s investigation by the National Audit Office, is now demanding BBC bosses provide an annual update to parliament on the progress of the project at Elstree Studios in Hertfordshire. The MPs also concluded that the BBC did not initially employ individuals with sufficient experience of running a major project and failed to allocate enough money to manage the risks and contingencies of the rebuild.

The committee chair, Meg Hillier, said: “The BBC made fundamental mistakes in planning and delivering E20, at significant extra cost to licence-fee payers. The apparent complacency with which the BBC approached the project is entirely at odds with EastEnders’ strategic importance to the corporation.

“It was a serious error at the outset not to consider exactly what skills would be needed to see E20 through. The resulting shortfall in key expertise set the tone for much of what followed. The revised completion date for E20 is still more than four years away and, as work continues, the BBC must demonstrate it now has a firm grip on the project’s costs and progress.”

A BBC spokesperson said: “As the report says, the project will deliver many benefits including an extended set to better reflect modern East End London, and suitability to film in HD for the first time. It has already delivered many vital improvements at BBC Elstree Centre which help other programmes. However, we strongly reject the notion that there has been any complacency in managing this project. Like any building work of this scale, there have been challenges along the way including construction market issues beyond our control and working on a brownfield site. We have made improvements to the project and continue to keep it under close scrutiny.”