UCL Institute for Environmental Design and Engineering


Condensation Risk – Impact of Improvements to Part L and Robust Details on Part C

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6 February 2017

Key facts

  • Funding Body/Client: The Department for Communities and the Local Government (DCLG)
  • Project Partners: Leeds Metropolitan University 
  • Total Project Value: N/A
  • UCL/IEDE Project Value Share: N/A
  • Duration: 2003-2005
  • Status: Complete

The Final Report summarises the main findings of the project ‘Impacts of Improvements to Part L and Robust Construction Details (RCD) on Part C’ (CI 71/6/1 BD2414).  The work consisted of a fieldwork element, undertaken by Leeds Metropolitan University and a modelling element carried out by University College London.

The fieldwork consisted of the analysis of design material and site surveys from 16 housing developments constructed to Part L 2002 and adopting the Robust Construction Detail route to compliance.

The modelling element of the project sought to identify the extent to which the ‘as built’ details give rise to a significantly increased condensation risk as compared to the relevant ‘standard’ robust construction details, as defined in the guidance. In addition to assessing ‘as built’ performance, the modelling phase of the project has investigated the suitability of the relevant calculation methods used to assess the risk of surface and interstitial condensation and mould growth.


PI: Tadj Oreszczyn

Co-I: Michael Davies and Ian Ridley

R: : Dejan Mumovic 


The following publications were produced as part of the work undertaken for this project:

  • Mumovic, D., Ridley, I., Oreszczyn, T. and Davies, M. (2006) Condensation Risk: Steady-State and Transient Hygrothermal Modelling Methods, Building Services Engineering and Technology, Volume 27, Issue 3, pp. 219-235
  • Mumovic, D., Davies, M., Ridley, I., Oreszczyn, T., Bell, M., Smith, M., Miles-Shenton, D. (2005) An Evaluation of Hygrothermal Performance of ‘standard’ and ‘as built’ construction details using steady-state and transient modelling, The 9th International Building Performance Simulation Association Conference, Montreal, Canada. 
  • Oreszczyn, T., Mumovic, D., Davies, M., Ridley, I., Bell, M., Smith, M., Miles-Shenton, D. (2005) Condensation Risk - Impacts of Improvements to Part L and Robust Construction Details (RCD) on Part C’ (CI 71/6/1 BD2414), DCLG, London 

The Final Report delivered for ODPM Building Regulations Division under the Building Operational Performance Framework. 


For further information please contact: Dejan Mumovic