Competition has pushed the construction sector into a "race to the bottom" where companies are taking on projects to win revenue rather than chase profit, says a top industry boss.

David Prentice was chief executive for seven years of NZX-listed Opus International Consultants, a multi-disciplinary infrastructure consultancy with 3000 staff that was bought by Canada's WSP Global in December.

Prentice, who is now leading the integration team at WSP Opus in Wellington, did not wish to comment specifically on issues at Fletcher Building, which last week announced further losses of $660 million at one of its divisions and said it would not be bidding on any new big projects.

But speaking about the construction industry generally, Scottish-born Prentice told the Herald earlier this month that the building market was becoming increasingly challenging.

"To design a building 20 years ago you'd need top structural engineers, your top architect, your top mechanical and electrical engineers. Nowadays a lot of this can be done using computer packages and what have you. So what it's doing is it's commoditising the design away from almost an art to a science," Prentice said.

"And what that means is that the margins that can be made on vertical infrastructure such as buildings is far less than it was before, therefore the need to make sure that you're absolutely on point when you come to do that work is essential because very quickly a very small margin can turn into a very big loss," he said.

"You always want increased competition but as long as increased competition isn't a race to the bottom. Unfortunately it has been a race to the bottom so people are going in incredibly tight to actually win revenue, so they've been chasing revenue as opposed to chasing profit."

These issues weren't isolated to New Zealand and around the world people in the building sector were having to work harder "to make an honest buck", he said.

Prentice believed that the way in which contracts were procured needed to change as right now the client or customer was pushing all the risk to a consultant or contractor.

"The best contracts without a shadow of a doubt are those contracts where risks are explicitly shared between all three parties, consultant, contractor and client ... I think the client and the customers, particularly central and local government, have got a long way to go in respect of maturity in how they procure projects."