Martin Sing is team lead for sustainability and energy at WSP in Canada, and Chessa Stevens is WSP’s national lead for built heritage in New Zealand. Malene Holmsgaard was director of building preservation at WSP in Denmark until December 2022.

There is a tension at the heart of heritage work. Regulations for listed buildings tend to restrict changes, making it difficult to reduce their energy use. But they must adhere to modern functional and energy-efficiency requirements as far as possible in order to remain viable and useful

The major rehabilitation of the Centre Block at the Canadian parliament in Ottawa is showing how low-carbon strategies can be adopted without altering a building’s character. The net-zero design includes waste heat recovery combined with an underground geo-exchange field, which stores surplus heat during the summer for use in the winter, as well as rainwater harvesting. The project is led by CENTRUS, a joint venture between WSP and HOK, and is due to complete by 2031