INSULAtE-project results - Improving energy efficiency of multifamily buildings, indoor environmental quality and occupant health

Within the EU, the Energy Performance of Buildings Directive (EPBD) and the
Energy Efficiency Directive are the main legislative tools aimed at reducing energy consumption in both new and existing buildings. National policies and programs exist in almost all European countries and are aimed at improving the energy efficiency of the building stock. Improved energy efficiency can also impact indoor environmental quality (IEQ) and occupants’ health and wellbeing. The INSULAtE-project (2010-2015) was focused on an assessment of improved energy efficiency of multifamily buildings, with the aim of demonstrating the effects of energy retrofits on IEQ and occupant health. This report presents the main results from the Finnish and Lithuanian case studies. Data from existing multi-family buildings (46 from Finland and 20 from Lithuania) were collected both before and (usually about one year) after energy retrofits, with temperature; ventilation and air tightness measurements; measurements of particle matter, chemical pollutants and radon; and analyses of mineral fibers and microbes from settled dust, i.e. objective and quantitative measures, combined with occupant surveys. Baseline results before the retrofits from the two countries demonstrated differences in IEQ and occupants’ satisfaction with it; for example, the relatively high indoor temperatures observed in Finnish apartments could indicate over heating, whereas elevated carbon dioxide concentrations found in some Lithuanian apartments indicated inadequate ventilation. After the retrofits, the average temperatures remained unchanged in Finland, while thermal conditions were significantly improved in Lithuania. Ventilation rates were slightly improved in Finnish case buildings, but remained similar or decreased in Lithuanian cases. Differences related to indoor air pollutant levels were found to be mainly due to temporal variations; however, in some cases the effects of indoor sources may have been increased after the retrofits. Occupants reported higher satisfaction with indoor air quality as well as less daily noise disturbance related to traffic or industry after the retrofits in both countries. In addition, occupants from Lithuania significantly more frequently reported a suitable winter temperature. However, it should be noted
that long term effects has not been assessed. Along with demonstrating the effects of improving energy efficiency on IEQ, the project has developed an assessment protocol that can be used to complement building investigations and energy audits. IEQ assessment could provide more comprehensive information about the condition and performance of the building as compared to the traditionally used building investigation and energy auditing protocols. The results of the project can be used to support the implementation of
policies and programmes related to energy performance of buildings in Europe.

Keywords: Energy efficiency, health, indoor environmental quality, multi-family
buildings, retrofit