Pat Toms' letter (NCE 6 September) raises a key point about taxation, but let me first correct some misunderstandings.
First, all of the six environmental performance indicators proposed by M4i are quantifiable and there is already some data about four of them for the industry to start making meaningful assessments of its performance. There is no doubt, however, that this is a subject which is still in its infancy and the industry is certainly being held back by lack of data in several critical areas - notably biodiversity and transport.
The whole point of launching these indicators is to get the industry to measure what it does - how else are we to know if we are ruining the planet or if we are actually reducing our impact on the environment?
Second, although there is a clear consensus about the assessment of buildings, the same cannot be said in respect of civil engineering projects.
Rather than delay the launch of the indicators until a suitable method has been found, M4i felt it was appropriate to go ahead with the indicators for buildings. Any help that the civil engineering sector can provide would be gratefully received.
Third, Pat Toms may be right that punitive taxes are the only way to force people to be sustainable, but that is no reason to avoid being objective about the performance of our industry's projects. The EPIs are a voluntary means of replacing wishful thinking with hard facts.
Rab Bennetts Chair, M4i Sustainability Working Group