Climate change poses a tremendous challenge to humanity; to stand a good chance of avoiding catastrophic levels of warming we need to decarbonise every area of our lives. The faster we can do this the better. At first glance this seems impossibly daunting, but many of the solutions to this decarbonisation challenge also offer tremendous opportunities. They could improve our lives at the same time as cutting our carbon emissions. Buildings are a perfect example of this. Heating, lighting and cooling buildings uses a lot of energy, currently about 40% of the energy used in Europe is for conditioning buildings. Well designed low-energy buildings can reduce energy use by up to 90%, while at the same time providing us with healthier and more comfortable places to live and work. This reduction in the energy use of buildings will make the transition to a zero-carbon economy easier and cheaper, but buildings can do even more than this. By carefully choosing materials for our buildings we can use them to sequester carbon from the atmosphere. Constructing new buildings and retrofitting old ones to the highest energy standards is a win-win-win situation. More comfortable homes, more productive work places, lower energy use and an easier transition to a zero-carbon energy system. This is what motivates me to always strive for better buildings.