Retrofits have been a major focus recently, but according to
some experts, "it's better to build a 'green'
house from the ground up," at least financially:
It may make more financial sense to build a green building from
scratch than invest your money in an existing building with limited
or no environmental credentials - or so say a growing band of
experts in the building and property trade.
. . .
And, while one might think erecting a new green building has a
bigger environmental impact than buying an existing one, it is a
myth, says Smith: "The argument that it's better to buy an
existing building than build new - since the ecological impact of a
building project is supposedly greater - is not true. The traffic
of maintenance teams having to return to a site for ongoing work is
much higher over the life-span of an old building than its new
counterpart.