The A38 in both directions will be limited to two lanes on the immediate approaches to the Markeaton junction. The A52 eastbound and westbound approaches will also be limited to two lanes on the approach. The Markeaton roundabout circulatory will be reduced to two lanes.
The restrictions will be in place 24 hours a day until 6am on Saturday 16 August.
Kevin Harvey, project manager for the scheme, said:
These limited lane closures are necessary so that we can get as much work completed as possible over the summer holidays, when the road is traditionally quieter.
We initially introduced the closures on 4 August for only a week, but work has progressed so well that we are taking this opportunity to undertake additional work and accelerate the scheme. We ask people for their continued patience whilst we carry out the work.
By increasing lane capacity, more vehicles will be able to access and exit the roundabout, improving traffic flow and journey times. Any further closures will be publicised in advance.
Members of the public should contact the Highways Agency Information Line on 0300 123 5000.
Journalists should contact the Highways Agency press office on 0844 693 1448 and use the menu to speak to the most appropriate press officer.