Helvetia Climate Bank publishes its hybrid mortgage attribution note

Helvetia Climate Bank has shared the methodology note behind its mortgage financed-emissions figures. The approach uses measured energy consumption for the largest exposures and energy performance certificate estimates for the rest of the book.

The note sets out how the split is chosen, how data quality scores are weighted, and how the bank plans to move more of the book onto measured data over time. Jonas Meier's guide to Category 15 boundaries covers the wider context.