Offsetting is not the great evil some climate change protesters would have it these past few weeks. Ideally, in our opinion, buildings should be constructed from sustainable, renewable and recycled materials only, but sometimes that is not practical. For example, when a development is sited in an earthquake zone. So, what's better, or to put it another way what's worse? To offset what can be e.g. the concrete used in the foundations, or to simply ignore its impact and focus on the positive carbon dioxide reduction elements used in a building's construction?

Most of us would agree, we think, that wherever possible renewable, recycled and sustainable materials should only be used – and the CO2 emitted in the materials used that are not zero-carbon during the construction process should be offset. Ongoing, the goal has to be to strive for zero-carbon homes on each and every new development, whether that is achieved by a combination of passive housing, good insulation, solar power and geo-thermal heating on a localised level, or by utilising elements thereof and linking into larger schemes where energy is provided solely from renewable zero-carbon sources. As ever, shades of grey are preferable to black and white.