Large construction sites that spill on to footpaths or need traffic diversions would also come under the rule, Mr Thomas said.
"It's not a major. It's only a relatively short period," Mr Thomas said.
Contractors Federation chief executive Jeremy Sole said there had been ample warning, but it would still be tough on companies.
"Contractors have just been through the global financial crisis hiatus, the pre-amalgamation [of the Super City] hiatus, the post-amalgamation hiatus, and now [they're] about to go into a Rugby World Cup hiatus," Mr Sole said.
"We need to make sure there's work to keep these guys alive or there's going to be nobody left."
The plan was an "eye opener" for the industry, he said.
"It would affect quite a few sites. It has to. There's always work going on around the city."
Hirepool manager Mark Gregory said work had already petered out in Auckland before the tournament and its moratorium.
"I know from the point of view of our business, it's [already] very, very quiet. No new holes are getting opened up," Mr Gregory said.
Many contractors had folded under the pressure, he said.
"Some have already gone away. Some have gone into liquidation."
Heb Construction contract manager David Loe said the lull in work was a continuation of the way the Super City operated.
"After the amalgamation [of Auckland councils] there was quite a reduction in work.
"They will put it down to efficiencies, but we will call it 'can't get themselves organised'," Mr Loe said.
Amalgamated Workers Union secretary Ray Bianchi said it was ridiculous for the city to be trying to put on a good look for the World Cup by driving out road cones.
"It's absolutely stupid. If [work] has to be done, it has to be done. If there's a burst sewer or water main, is it just going to stay there until the stupid game of rugby finishes?
"It's like getting the bums [homeless] off the streets."
