"Whether the economics of it ... and whether the 1.2 or 1.5 million people can support it - I'm not quite sure. I would have my concerns," he says, indicating it could be planned too soon.
"If the economics are not good, either the ratepayer or the taxpayer has to subsidise it and it doesn't run at its optimum because it doesn't have a flow-through and it makes it difficult for the users to create an economic advantage."
Yet Fletcher stands to gain potentially, being the largest commercial builder in New Zealand and having won and completed the New Lynn railway station and transport interchange upgrade in a consortium with others on the $190 million project.
Yes, Ling says, Fletcher might win a share of the CRL job - "you never know" - but that does not change his view about the wisdom or viability of its timing.
Overall, the number of big New Zealand building jobs is relatively scarce.
"It's a very tight market right now and the Government is slowing down as they pursue through to 2014/15 generating a surplus or breaking even. Residential construction is not really increasing and Christchurch is quite slow."
A division of Fletcher Construction is the project manager for the Canterbury Home Repair Programme. That work is carried out under contract to EQC. Ling says the EQC work is going well and is on target.
"On the infrastructure repairs, such as pipes - that's running at half the rate it needs to run at. In essence, the Government decided if they're going to spend $2.5 billion repairing it, they would need to replace the whole lot and that started a process of a year of planning and it's just coming to an end now.
So the work is starting to ramp up.
"And lastly on commercial rebuilding, it has not started really. It's about resolving a lot of insurance negotiations and about commercial landlowners wanting to rebuild in Christchurch and it's painfully slow," Ling says.
In September, Mark Adamson will take over as Fletcher Building CEO. Ling will return to Melbourne with no definite plans, other than to take a break.
His intention is to gradually sell some of the approximately 200,000 Fletcher shares he owns, "I probably need to diversify my portfolio but $6 is a lousy share price. I'll wait for appreciation."