Official and informal tools to embed performance in the design of low carbon buildings. An ethnographic study in England and Wales

• Teams are identifying energy indicators by heuristics and performance-based tools.
• Experience and collective knowledge help to understand and embed energy performance.
• Informal and qualitative tools support the use of official calculation methods.
• Simulation may be deployed only for compliance though it could be also a design aid.
• Official instruments may not get integrated in the process, becoming prescriptions.

The British low carbon policy aims to achieve zero carbon buildings by 2020. This investigation what building designers are doing to embed the low carbon policy aspirations in routine project design, based on a comparative ethnographic study. The researcher documented the design process observed in four non-domestic buildings procured by design and build method. This article documents the tools deployed by building designers to embed energy performance. The analysis of the design tools unveils the low carbon problem-solving process. A number of informal tools and practices were found to be used in the design process to assist the outline of the energy aspirations, understanding and calculation of energy performance. These informal mechanisms supported the adoption of regulations and compliance tools by building designers. The field data suggests that there are pre-existing practices and designers' preferences that are the foreground where the policy requirements are to be incorporated. It is necessary that the policy model is informed by the designers' dimension to overcome the non-technical barriers that hinder the implementation of low carbon policies.