Jason Palmer was an ‘Evaluator’ for Innovate UK’s Building Performance Evaluation Programme. This means he helps monitoring teams get to grips with energy data for their buildings – along with data about thermal performance, occupant satisfaction, air-tightness, lighting, embodied carbon and other measurable outcomes from building projects.
It is hard to generalise across all projects, but the programme generated important insights into where even buildings where the project team prioritises carbon performance can falter. Procurement, commissioning and handover are at least as problematic as the technical side of low carbon design.
The Cambridge Energy team looked across all non-domestic evaluation projects funded by Innovate UK, analysed the data emerging, and drew out conclusions that almost certainly apply to other commercial and public buildings. We identified an evidence-based ‘performance gap’ averaging 3.5 across the non-domestic portfolio.
This means that actual energy use is three-and-a-half times higher than the design estimate, on average, and sometimes considerably higher.
We went on to do similar performance analysis and diagnostics work on the domestic portfolio, and found that even simpler domestic buildings still fall a long way short of design estimates, with a typical new home using 2.5 times more energy than the design estimate.