Drivers using part of the A4 in Berkshire face six weeks of disruption while utilities are connected to a new housing development.
The A4 Bath Road at Speen, near Newbury, Berkshire, will be closed 24 hours a day from Monday until 8 June.
Residents living nearby have voiced concerns about parking and access to their homes.
West Berkshire Council said it was not possible to carry out the work any quicker due to the number of pipes and cables already in the ground at the site.
The work is to install water and gas mains to 118 new homes which form part of the Lapwing Green development, close to the junction with the A34.
The planned diversion will take traffic four miles around the area to the Chievley interchange of the A34.
West Berkshire Council said: "There is a significant amount of apparatus to install… to provide services to the new development.
"Due to the location of the services, there is not enough remaining road width to keep the road open under any other form of traffic management."