Indoor air quality, thermal comfort and daylight policies on the way to nZEB – status of selected MS and future policy recommendations

Panel: 6. Policies and programmes towards a zero-energy building stock

This is a peer-reviewed paper.

Authors:
Sara Kunkel, Buildings Performance Institute (BPIE), Belgium
Eleni Kontonasiou, BPIE – Buildings Performance Institute Europe

Abstract

Buildings are getting tighter and better insulated in order to reduce their energy needs caused by heat loss via transmission and uncontrolled air flows. Better insulated buildings also increase the risk of overheating, and therefore the prevention of overheating becomes increasingly important. At the same time humans need minimal air exchange rates for a healthy indoor climate and protection of the building fabric. There is also increasing awareness of the importance of daylight on health.

It needs integral planning and good building codes to adequately address these challenges. Projects already prove that buildings can be energy efficient and at the same time contribute to outstanding indoor air quality and comfort. The EPBD, 2010/31/EU calls the Member States (MS) to further improve the regulatory and policy frameworks in order to reach nearly zero-energy buildings and indicates that indoor climate conditions have to be considered when putting in place minimum energy requirements. However, there are currently no clear requirements for indoor climate conditions in buildings.

This technical paper about indoor air quality, thermal comfort and daylight requirements in 8 selected MS (BE – Brussels Region, DK, FR, DE, IT, PL, SE, UK – England and Wales) addresses a range of parameters of these topics that are vital for buildings and their inhabitants.

The results of the analysis show that all studied MS have at least a basic reference to IAQ included in their building codes. Minimum ventilation rates are required or recommended in all 8 MS and precise airtightness requirements are in place in 6 MS (BE, DK, FR, SE, PL, UK). Concerning thermal comfort indicators, indoor temperature requirements or recommendations range between 16°C (PL) and 28°C (FR) and recommendations about humidity are given in 6 MS (DE, PL, IT, SE, UK). All 8 MS include at least a basic reference to daylight in their building codes mainly referring to a minimum share of window area per floor area and minimum levels of daylight.

Based on the findings it can be concluded that indoor health and comfort aspects should be considered to a greater extent in the EU and national building codes.