Exceedance Degree-Hours: A new method for assessing long-term thermal conditions

Area of Science:

• Building Science
• Environmental Engineering
• Human Comfort Studies

Background:

• Existing discomfort indices often fail to meet all requirements for comprehensive thermal comfort assessment.
• Limitations include difficulty incorporating all environmental and personal factors and adaptability to various comfort models.

Purpose of the Study:

• To develop a novel discomfort index, Exceedance Degree-Hours, addressing limitations of current indices.
• To create an index capable of assessing thermal comfort in mixed-mode buildings and adaptable to diverse comfort definitions.

Main Methods:

• Development of the "Exceedance Degree-Hours" index, incorporating six key environmental and personal factors.
• Utilization of an equivalent temperature index to capture varying discomfort severity.
• Comparison of the proposed index with existing standard discomfort indices.

Main Results:

• The Exceedance Degree-Hours index successfully accounts for all six main environmental and personal factors.
• It demonstrates superior capability in capturing discomfort severity variations compared to existing indices.
• The index is shown to be compatible with multiple comfort definitions and applicable to mixed-mode buildings.

Conclusions:

• The Exceedance Degree-Hours index offers a more comprehensive and flexible approach to discomfort assessment.
• It provides a single, valuable metric for evaluating thermal comfort, particularly in complex building environments like mixed-mode buildings.