Construction companies have to deal with a mountain of energy efficiency legislation as governments try to move to a low-carbon future. Buildings account for 45% of all UK greenhouse gas emissions such as carbon dioxide and methane, so the drive for new energy efficient building stock is understandable. However it is important to remember that an estimated 70% of existing buildings will still be in use by 2080, so the focus on new-build is perhaps misguided. Some people claim that the low-hanging fruit is to be found by spending time and effort up-rating the efficiency of existing building stock. Whilst policy makers are aware of the huge potential of reducing carbon emissions by writing legislation on existing buildings, they admit that this would involve more heavy-handed intervention and public resistance than if they levelled their sights on the construction of new buildings. All new building construction requires approval from authorities and regulating bodies, so this naturally lends itself to an expansion of rules on energy and carbon emissions. As with most things, the issue comes down to cost and political convenience.

Question: Energy efficiency legislation for new construction is more onerous than for existing buildings.
Options:
A. true, B. false, C. uncertain
Answer: "C"