Wales & West Utilities began upgrading gas pipes in Dinas Powys on July 6, focusing initially on Millbrook Close and Caerleon Road.
The work is part of a wider more than £1.1 million investment programme to improve gas infrastructure across the area, with a benefit to customers according to Wales & West Utilities.
Andrew Coleman, of Wales & West Utilities, said: “We’re investing in our gas network to ensure it remains safe, reliable and fit for the future for the customers we serve.
“We’ll be keeping the local community updated on these works and working with the local authority, and other key partners, to keep disruption to a minimum.”
The project has been planned in conjunction with Vale of Glamorgan Council.
Work will move to Cardiff Road during the school holidays, starting July 18.
Rolling temporary traffic lights will be in operation from that date, and motorists are advised to allow sufficient travel time.
Mr Coleman said: “We understand our work can cause disruption, but it is essential to maintain a resilient gas network that households and business can rely on every day.
“While much of the gas network is out of sight, it plays a vital role in daily life – from heating homes to cooking meals.”
The scheme is expected to be completed in October, subject to progress and weather conditions.
Mr Coleman said: “By completing this work now, barring any emergency repairs, we can avoid returning to the area and causing further disruption to the local community for decades.”
Wales & West Utilities delivers energy to more than 7.5 million people across Wales and the south west of England.
