We all know buildings are part of the global warming problem, but many people don’t recognize how central they are to the solution. A recent UNEP report — “Buildings and Climate Change: Status, Challenges and Opportunities” — shines light on how relevant and accessible building-related climate change solutions are. Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said:

By some conservative estimates, the building sector world-wide could deliver emission reductions of 1.8 billion tonnes of C02. A more aggressive energy efficiency policy might deliver over two billion tonnes or close to three times the amount scheduled to be reduced under the Kyoto Protocol.

The International Energy Agency estimates that a total global switch to compact fluorescent bulbs would in 2010 deliver C02 savings of 470 million tonnes or slightly over half of the Kyoto reductions. We have to ask what the hurdles are — if any — to achieving such positive low cost change and set about decisively and swiftly to overcome them, if they exist at all.

I realize Kyoto is not our final goal, but the point here is the potential for harvesting carbon reductions from buildings is immense, and most of solutions are 1) with us already and 2) relatively low-cost to deploy. The challenge is largely changing practices. But as Achim notes, the hurdles in the building sector, unlike some other sectors, may not be very substantial.

What I’ve read of the report is not that new — it synthesizes ideas and approaches already out there (and it missed some I might have liked to see). What is important is that it contextualizes the impact and opportunities of buildings as compared with other sectors. How we build and operate buildings is one of the most important tools for carbon reduction and cannot be left off the table as we pursue the utility, automotive, and manufacturing industries.

As might be expected from UNEP, the report has a refreshingly international approach. It spells out the different challenges facing developed and developing countries. In particular, developed countries above all need to address their existing stock of buildings, while developing countries need to focus on new construction practices.

The recommendations are mostly what you’d expect — policies, regulations, economic tools, technology transfer, new technologies in the public sector, and education and awareness raising. There are two I was pleased to see, though — understanding human behavior and benchmarking.

On human behavior:

No matter how well-designed a building is, its energy performance will in the end very much depend on how the people living in, working in, or otherwise using the building are behaving and to what extent they make use of energy efficiency provisions. In other words: improved energy efficiency requires conscious choices and responsible use of facilities. The better one understands the logic behind human behavior, the better chances one has to succeed with technologies.

On benchmarking:

The understanding of what constitutes a sustainable building is now fairly well developed, and in some countries certification systems have been adopted based on specific criteria related to the use of materials, water, energy, comfort etc. Not surprisingly, however, most countries lack such systems, and there is no universal definition of what constitutes a sustainable building … There is a clear need to quantify what may constitute an energy efficient building under different conditions (new/old buildings, different climate zones, etc.), and to quantify the associated benefits in economic terms, as well as in terms of greenhouse gas emission reductions.