As temperatures reached 37 degrees on Tuesday, Roads ACT crews were at work at sites around Canberra.

At Wanniassa, bitumen worker Richard Silwinski said working with hot material with no shade made this month a tough one.

"The bitumen we are working with today is over 160 degrees and when it is a hot day the close contact makes it feel much hotter," Mr Silwinski said.

Despite the heat, road workers are expected to monitor their own health and wellbeing, and alert superiors if they feel unwell.

Manager of road maintenance Ken Marshall said staff were well informed of safe work practices in hot weather and procedures were regularly advised.

"All of the workers know how to keep themselves safe in hot weather conditions," he said.

"If the weather is too hot, the responsibility is with the worker to let us know."

Mr Marshall said there was no fixed temperature in which employees were sent home, but early starts or night work could be used to minimise time in the sun.

"If we can give relief from the heat, we do, but sometimes it is not possible and these blokes do a great job with coping in the heat," he said.

It's not just those laying the hot bitumen who have to cope. Traffic controller Jon Toth stands in direct sunlight for more than seven hours a day with only occasional respite during shaded breaks.

Mr Toth said during Canberra's heatwave it was particularly important to stay hydrated.

"I try to take a short break every two hours because prevention is the best method but it does get very hot," he said.

Meanwhile, Territory and Municipal Services said work on resurfacing parts of Tuggeranong Parkway would start at 5am on Wednesday and alternative routes should be sought to avoid delays.

The work, which will finish by 4pm, will be carried out on southbound lanes between Hindmarsh Drive and Sulwood Drive on Wednesday, and on the northbound lanes on Thursday and Friday. There will be reduced speed limits and traffic will be restricted to one lane.