Indoor climate guidelines in the Netherlands: Developments towards adaptive thermal comfort

Purpose – This paper sets out to highlight several aspects of a project, aimed at developing an advanced thermal comfort guideline, based on the adaptive thermal comfort theory. Design/methodology/approach – The paper introduces the new Dutch adaptive guideline for thermal comfort. The initial method exceeding hours (TO) is discussed, as well as the more recent method of weighted temperature exceeding hours (GTO). An evaluation of the practical and theoretical shortcomings of the TO and GTO methods is discussed, as well as the rationale behind the adaptive ATG guideline. Furthermore, the results are presented of computer simulations in which the predictions of the different methods are compared. Productivity effects of the new guideline are also discussed, as well as the implications for cooling system sizing and energy efficiency. Findings – The adaptive temperature limits (ATG) guidelines appears to be a more reliable method for the assessment of thermal comfort, in particular for passive, free-running buildings, compared with the PMV-based method of weighted temperature exceeding hours (GTO). Furthermore, the ATG method allows for a wider temperature range for Alpha type buildings and gives more opportunity for the development of sustainable, naturally ventilated buildings and limiting cooling energy. Research limitations/implications – Although the new ATG method shows promising results, more research is needed. The exact distinction between Alpha and Beta is still subject to further research, as well as the question whether a certain amount of exceeding hours of the ATG limits should be accepted. Practical implications – The ATG method is being used in The Netherlands for the assessment of thermal comfort in the design stage as well as in the assessment of the performance of buildings in use. Originality/value – This paper discusses the first application of the adaptive thermal comfort theory in a practical guideline.