In a LinkedIn message from his home he added that it was essential the industry kept operating to protect millions of jobs.
He said that he recognised employees were faced with a challenging situation and total them to stagger journey times to avoid peak travel times.
In a social media post, he said: “I’m now self-isolating, working from home, after my wife Debbi came down with some of the symptoms herself, although we think it’s just a cold.
“It’s vital that we all follow government guidance – not just to protect ourselves, but to ensure that we’re not putting others at risk.”
Reynolds added: “It’s also important that our industry is able to keep operating throughout this difficult time, as long as it can do so responsibly, to protect the millions of jobs it supports.
“In order to do so, we’ve introduced measures to ensure that people can work safely, including rigorous cleaning routines and carefully planned work rotas.
“I am very conscious that there are many people delivering essential work for Mace who are still travelling into work every day,” he added.
“Keeping our projects open as long as possible is key to the long-term sustainability of our business, but we recognise that it is a challenging situation.
“Please make sure you are staggering your journey times and avoiding peak travel times as much as possible. ”