Townsend's vision places BREEAM at the centre of a data repository for all key stages of a building project. He saw a time when spatial planning, statutory planning and applications, post construction reviews and post occupancy evaluation all feed into an online central BREEAM database.
In advancing this ambition, Townsend argued that "We are only going to be successful in actually making better spaces for people and communities…if we understand what we got right. Communities need to engage with local authorities and developers, forming relationships with organisations to create policies that will drive change."
"If we are serious about sustainability, it's about making sure we learn," added Townsend. "It's important that we know what works and what isn't sustainable."
This, of course, is an ambition shared internationally, not just by BRE Global. LEED, via the US-GBC, has similar ambitions for cross-scale assessments.
"Our goal" said Chris Pyke, "is market transformation. We want to change the conditions of the built environment, creating communities and buildings that are better for people and the environment."
The US-GBC has spent eight years incubating a set of new tools and approaches to achieve this object, and is now into "full active participation and public comment" on three interlocking LEED tools: LEED for New Construction, LEED for New Development, and LEED for Interiors.
"In LEED 2012, we have identified a different set of outcomes (to these tools) while applying same constructs. We are applying it to a fancy database that allows it to associate strategies with outcomes across multiple criteria: such as control, magnitude, and duration. Fundamentally, it's a matrix of things you can do, things you want to abate, the associations, and a way of knowing how successful a strategy will be.
As the indexes are calculated, at each scale - one for new construction, one for neighbourhood, and one for commercial interiors - the results they generate will be complementary," explained Pyke. "At neighbourhood scale I'm talking about transport, infrastructure and land programming, at the single building level about design operation and the transport and construction of the building, while at the commercial space level it's about building services systems and purchasing."
It seems LEED 2012 will deliver pretty much what BREEAM is aspiring to do: a very close-coupled rating system that can create an equivalent index for a neighbourhood, new construction and interiors of a building, all of which can be used to inform decision-making at various scales.
The grand ambitions of the assessment providers require the mechanics of the assessment process - and the metrics that underpin the credits and the weightings - to be scientifically and statistically accurate, robust and repeatable across different contexts.
Which brings us neatly to the accuracy of measurement of environmental factors and the accuracy of the tools and computer models. And to Reading University's Howard Darby, who has been studying the standards and software tools for assessing operational and embodied greenhouse gas emissions.
Darby found a lack of a standardised approach to the calculation of embodied energy and of reliable data on emission factors for building materials and processes. "There is a lack of a consistent and accepted approach to the calculation of embodied energy" said Darby, "and the relationship and interaction between it and operational energy is not well understood. There is also considerable uncertainty and variability in the available information on emission factors for building materials and processes."
Darby based his analysis on a book storage building in Swindon. Completed in 2010, the building is a 11 578 m2 steel-framed structure on mass-concrete foundations, housing a mix of offices and stores. Darby studied the building's fixed structural and services elements, (ignoring the furniture and fittings) and ran the properties through the simulation packages CES Eco-selector, EA Carbon Calculator (a free on-line package), and Envest 2 from the BRE. Darby analysed each program for its suitability for all phases of the building's life, the transparency of benchmark data, and the programs' ability to provide a good breakdown of results.
Darby relied on the generic embodied-energy sources promoted by the steel and timber associations. He also based his assessments on a typical building life-cycle, assumed natural sources of construction raw material, and factored in conventional means of transport. He then ran the building through a conventional life cycle, from construction through to occupation, maintenance, demolition and re-use.