UCL Institute for Environmental Design and Engineering


Uncertainty in steady state whole building heat loss measurements (co-heating tests)

30 November 2016

By Samuel Stamp


Robert Lowe

Hector Altamirano

2011 – 2014

This PhD research project aims to understand the sources of uncertainty in steady state or ‘co-heating’ heat loss measurements. These whole building heat loss measurements have been used to uncover previously misunderstood heat loss mechanisms (i.e. the party wall bypass) and unearth evidence of a fabric performance gap – where measured heat loss is commonly significantly higher than design predictions.

However, as with any measurement it is important to understand the limits and uncertainties within the measurement and the existing method. This is explored through the use of both simulated and field tests. The aims of this research are:

  • To identify sources of uncertainty – experimental and weather driven
  • Assess the impact, nature and scale of each source of uncertainty 
  • Understand the interactions between these sources of uncertainty and building type
  • Provide recommendations on test protocol, analysis and reporting to limit the impact of these sources of uncertainty 
  • Suggest how and when co-heating tests can be used successfully, and what research questions they can successfully answer?

Ultimately, it is hoped the conclusions of this research will allow greater understanding of such steady state tests, such they can be used to help close the performance gap in an informative and productive manner.