Ross Holleron states (12 December, page 59) that “Hanham Hall … will produce excess heat from its combined heat and power system in summer months. Some of this will supply the hall and a communal glass house, but the rest will have to be dumped.”

This is news to the project team. We have been working with some of the neighbouring building owners with a view to selling excess heat to them.

As to the idea of new build cross-funding the upgrading of the existing stock, why should this be? I can understand the reason for section 106 agreements, because a development relies on existing facilities. But there is no financial link between the upgrading of existing stock and the development of new buildings, nor should there be. What we need to do is to unlock

the financing of the upgrades, not use this as an excuse to tax developers who are already struggling to keep in business.

By the way, the image of Hanham Hall attached to the article should have been credited to Barratt.

Rory Bergin, head of sustainability and innovation, HTA Architects