NOISE levels outside some homes on a forthcoming 370-property estate would be so high that residents would need to avoid opening their windows, a report concluded.

An application to Darlington Borough Council to meet sound conditions imposed on developer Persimmon’s scheme off the A167 Durham Road at Berrymead Farm states if windows in numerous homes beside the road are opened noise insulation would reduce, resulting in daytime levels over the required standard within habitable rooms.

The consultants’ report concludes “an alternative ventilation system should be installed in the dwellings”.

While environmental campaigners say the demands of addressing the climate emergency will require most homes to have heat recovery and mechanical ventilation systems fitted, there is a huge difference between not needing to and not being able to open windows.

Darlington council’s Green Party leader Councillor Matthew Snedker said: “Academic research shows that traffic noise can cause long-term health problems, such as high blood pressure, cardiovascular disease and type 2 diabetes.”

Cllr Snedker said if the council rose to the Government’s challenge of seeing 50 per cent of journeys being made by cycling or walking by 2030 and took advantage of growing numbers of people working from home there is no reason that residents along Durham Road, and all other main roads in the town, could not benefit from a cut in traffic, noise and pollution.

Asked if it was acceptable for developers to build properties where the windows cannot be opened due to noise levels, economy cabinet member Councillor Alan Marshall said the planning application and noise report remained under consideration.

He said: “Advice on the acceptability of the conclusions of the report has been sought from the environmental health team and they will report back to the planning officer for consideration before a recommendation is arrived at.”