With the government having set a target for all new homes to be "zero carbon " by 2016 and all new buildings to be "zero carbon" by 2019 the clock is ticking for the building industry to start delivering emission free homes.

But can those targets be met, and if so how?

BusinessGreen.com visited last week's Think 08 sustainable building conference and caught up with some of the leading figures from across the industry and asked how confident they were that a "zero carbon" built environment could be developed.

Keith Clarke, chief executive of engineering and design consultancy Atkins
"We can achieve approximately a 30 to 40 per cent cut in carbon emissions using current best practices, but we need to embed carbon into the design process to get close to zero carbon building and we have to do it quickly. Professional bodies have a key role. We can't trust financial institutions to solve climate change by carbon trading, but we should base the future of the world on professional people with tangible skills, going through a learning process faster than ever before."

Mike Peasland, director of building giant Balfour Beatty
"In the UK, the construction industry has no common method of measuring or reporting on carbon or energy. Zero carbon is achievable depending on how you measure it and whether you count carbon offsets. The government needs to define what zero carbon means as the industry needs one definition of lifecycle assessment. There is a mindset where green means expensive. We need to work together to change that in the construction industry itself and all parts of the supply chain."

Paul King, chief executive of UK Green Building Council
"The challenge of zero carbon is a combination of danger and opportunity - 45 per cent of UK emissions are from buildings, but the built environment is also the best opportunity to cut global emissions by half according to the IPCC. You have to be lean, mean and green. To be lean your build design should halve energy demand. To be mean the building should be twice as efficient in materials and services. And to be green you should halve the carbon content of fuel needed to power and heat the building. If this is done you reduce emissions of a building to an eighth of conventional figures. Business as usual is not acceptable and won't get us to zero carbon in a cost-effective way."

Murray Coleman, UK chief executive of project management and construction firm Bovis Lend Lease
"We have four issues to tangibly manage our environmental impact over a three year period. We will reduce carbon emissions by 20 per cent based on our 2008 baseline, measured by the Carbon Trust. We're doing this by using gas power generators and temporary LED lighting, which has cut lighting carbon emissions by 40 per cent. We are reducing the amount of waste going to landfill by 70 per cent based on 2007 numbers and are using sustainable design according to BREEAM recommendations. We are also using materials that are responsibly sourced and have industry wide certification. All companies need a roadmap and then importantly must stick to the plan to see real change."