IEA EBC Annex 68

The overall objective of the IEA EBC Annex 68” Project, “Indoor Air Quality Design and Control in Low Energy Residential Buildings”, has been to develop the fundamental basis for optimal design and control strategies for good Indoor Air Quality (IAQ) in highly energy efficient residential buildings, and to disseminate this information for use in practice. The project was defined in 2015, the working phase lasted for the years 2016-19, and the project was concluded with publications on 2020.

The IEA EBC Annex 68 project on “Indoor Air Quality Design and Control in Low Energy Residential Buildings” has been recently completed. The project considered indoor air pollution loads in dwellings, particularly how such pollutants are emitted in dependency of the hygrothermal conditions: temperature, moisture and air flows. Thus, a proper understanding of the mutual interactions between hygrothermal conditions and pollutants was needed to obtain optimal paradigms for demand-controlled ventilation.

The overall objective of the “Annex 68” Project, which belongs to the International Energy Agency’s “Energy in Buildings and Communities” Implementing Agreement, has been to develop the fundamental basis for optimal design and control strategies for good Indoor Air Quality (IAQ) in highly energy efficient residential buildings, and to disseminate this information in a practically applicable guide. The strategies shall facilitate the possibility to design and operate residential buildings with minimal energy use, while ensuring impeccable indoor climates.

The objective of Subtask 4 in the IEA EBC Annec 68 was to integrate knowledge and results from remaining Subtasks and present them in the context with current knowledge. The focus of the Subtask 4 was on practitioners dealing with ensuring high Indoor Air Quality (IAQ) in modern low-energy residences, the demands and challenges they meet during daily work. This especially includes architects and ventilation designers, facility managers, property developers and employees of public authorities. This publication is a result of Subtask 4’s work.

The objective of present work was to develop the metric that assess the performance of solutions securing high indoor air quality in low-energy (modern) residential buildings. This was achieved by summarizing data on the levels and types of gaseous pollutants and particulate matter in low-energy buildings and comparing them with the existing exposure limits for pollutants.

The objectives of Subtask 4 are to develop design and control strategies for energy efficient ventilation in residential buildings which ensure high indoor air quality. The strategies must go beyond the current common practice and actively utilize recent research findings regarding indoor air pollutants and combined heat, air and moisture transfer as well as benefit from recent advances in sensor technology and controls.

The objectives of Subtask 3 Modeling are to improve the understanding and develop prediction models on the impacts of outdoor pollutants, thermal environment, building materials and envelope, and indoor furnishing and occupant activities on the indoor air quality, and the energy necessary to achieve the desired IAQ level in residential buildings, considering the IAQ metrics and pollution loads to be developed in Subtask 1 and 2, respectively.

First the Subtask will organize a literature survey and make researcher contacts to gather relevant data and existing knowledge on major pollutant sources and loads in buildings, including models. Laboratory testing and model setup to provide examples of new types of data which shall be beneficial to improve knowledge on combined effects that must be taken into consideration in order to achieve new paradigms for energy optimal operation of buildings.

Subtask 1 of IEA EBC Annex 68 will aim at defining the metrics to enable a proper consideration of both energy and IAQ benefit in building design and operation