Indoor Environmental Quality

This document provides practitioners with an overview of the current status of national building codes regarding indoor environmental quality (IEQ) and energy performance, with a focus on how they address overheating and ventilative cooling in buildings. The review focuses primarily on building codes applicable to new buildings in cold and moderate climates, where regulations have traditionally prioritized heating performance.

Noticeably higher concentrations of gaseous pollutants were measured in bedrooms than living rooms, and in winter than summer, where p-values were found to be of a stringent significance (average p = 0.008). PM2.5 concentrations were found to be exceeding the WHO 24-h average threshold of 15 µg/m3 in kitchens for the week-long monitoring time (92% in winter, 51% in summer).

A composite rating scheme for indoor environmental quality (IEQ) can help provide a summary picture of buildings for occupants, inform the building managers regarding IEQ performance that need attention, and raise awareness on regarding the importance of IEQ parameters. The TAIL IEQ rating scheme has been designed to communicate such aspects in a simple, easy to use manner. 

There is a pressing need for large-scale energy retrofits in domestic dwellings to reduce carbon emissions. However, these retrofit strategies must be carefully balanced against the embodied carbon, operational energy, and indoor environmental quality in dwellings. This research aims to analyse the implications of indoor environmental quality arising from energy retrofit scenarios in the Irish context. Building physics simulations will determine a range of pre and post-energy retrofit scenarios and address the implications under various scenarios.

Most current environmental control systems installed in buildings aim to create a uniform IEQ, disregarding the large interpersonal and intrapersonal variability in occupants’ thermal, visual, acoustics & air quality requirements. By creating occupant micro-environments that respond to individual preferences, and relaxing the surrounding space, personalized environmental control systems (PECS) can satisfy all occupants with relatively low-energy input.

Personalized Environmental Control Systems (PECS) have advantages of controlling the localized environment at occupants’ workstation by their preference instead of conditioning an entire room. A new IEA EBC Annex (Annex 87 - Energy and Indoor Environmental Quality Performance of Personalised Environmental Control Systems) has recently started to establish design criteria and operation guidelines for PECS and to quantify their benefits. This topical session will provide an introduction to the objective/scope, activities, and intended outputs of the annex.

Most New Zealand schools are designed to be naturally ventilated, using openable windows (Ministry of Education Design Quality Standard Guidelines). Furthermore, they must meet the New Zealand Building Code Clause G4 - Ventilation. Clause G4 requires the “net openable area of windows in a classroom to be no less than 5% of the combined habitable floor area to achieve sufficient ventilation”. Although they are designed to code, there is no end-user operational or systems requirement for them to be opened.

In recent years, naturally ventilated glass façades have become a common feature in the design and retrofit of large-scale non-residential buildings, integrating architectural aesthetics and energy efficiency. These façade systems are complex and multifaceted. Thus, introducing them in buildings poses many challenges from economic, engineering, health and behavioural perspectives that can reduce optimal building performance. Building occupant behaviour and preferences are important contributors to the gap between the predicted and actual building energy performance.

Considering all aspects of indoor environmental comfort (thermal, visual, acoustical and air quality) and their interactions, questionnaires aiming at detecting assess people's perception of indoor environmental quality (IEQ), well-being and satisfaction should be designed in a more homogeneous way. In particular, the choice of the questions, response options and scales adopted must satisfy consistency criteria between different IEQ areas, but also allow a direct correlation to specific measurable quantities.