Energy Retrofits in Multi-family Buildings in North-east Europe: The Impacts on Thermal Conditions

AbstractWe have conducted a project to develop a common protocol for indoor environmental quality (IEQ) assessment and to assess the effects of energy retrofits on IEQ. This paper focuses on thermal comfort, which was first assessed based on 2-month continuous monitoring in 16 multi-family buildings (94 apartments) in Finland and 20 buildings (96 apartments) in Lithuania during heating season before retrofits. In addition, corresponding data after retrofits were available from three buildings (17 apartments) from Finland and seven (30 apartments) from Lithuania. Two data loggers per apartment were placed to evaluate Tw and RHw (warm area), and Tc and RHc (coldest spot). Questionnaire data regarding housing quality and health were collected from the occupants. The results before retrofits indicated high Tw (>23°C) for a large proportion of time in Finnish apartments, whereas opposite trend was observed in Lithuania. After retrofits, proportion of time with high Tw was higher while proportion of apartments with low RHw was lower in Finland, whereas in Lithuania, about one fourth of the apartments had higher Tw and RHw, hence fulfilling the national guidelines. The average absolute humidity was higher after retrofits in both countries, especially in Lithuania (by 15%). Occupant responses indicated improved thermal comfort. Therefore, potential effects of energy retrofits on occupants’ thermal environment and satisfaction were demonstrated, and simply adjusting indoor temperature could help to save energy. Further analysis is needed to include the effects of outdoor conditions, as well as overall IEQ to the assessment

Improving energy efficiency of multi-family buildings, impacts on indoor environmental quality and health

Ilmestynyt suomenkielisenä nimellä Asuinkerrostalojen energiatehokkuuden parantaminen ja sen vaikutukset sisäympäristön laatuun ja terveellisyyteen (Tutkimuksesta tiiviisti 14/2016

Daugiabučių pastatų energinio efektyvumo gerinimas, poveikis vidaus aplinkos kokybei ir sveikatai

Ilmestynyt suomenkielisenä nimellä Asuinkerrostalojen energiatehokkuuden parantaminen ja sen vaikutukset sisäympäristön laatuun ja terveellisyyteen (Tutkimuksesta tiiviisti 14/2016

Field Measurements and Numerical Simulation for the Definition of the Thermal Stratification and Ventilation Performance in a Mechanically Ventilated Sports Hall

Sports halls must meet strict requirements for energy and indoor air quality (IAQ); therefore, there is a great challenge in the design of the heating, ventilation, and air conditioning (HVAC) systems of such buildings. IAQ in sports halls may be affected by thermal stratification, pollutants from different sources, the maintenance of building, and the HVAC system of the building, as well as by the activities performed inside the building. The aim of this study is to investigate thermal stratification conditions in accordance with the performance of the HVAC systems in the basketball training hall of Žalgirio Arena, Kaunas in Lithuania. Field measurements including temperature, relative humidity, and CO2 concentration were implemented between January and February in 2017. The temperature and relative humidity were measured at different heights (0.1, 1.7, 2.5, 3.9, 5.4, and 6.9 m) and at five different locations in the arena. Experimental results show that mixing the ventilation application together with air heating results in higher temperatures in the occupied zone than in the case of air heating without ventilation. Computational fluid dynamics (CFD) simulations revealed that using the same heating output as for warm air heating and underfloor heating, combined with mechanical mixing or displacement ventilation, ensures higher temperatures in the occupied zone, creating a potential for energy saving. An increase of air temperature was noticed from 3.9 m upwards. Since CO2 concentration near the ceiling was permissible, the study concluded that it is possible to recycle the air from the mentioned zone and use it again by mixing with the air of lower layers, thus saving energy for air heating

Impacts of energy retrofits on indoor CO2 concentration and air change rate : 10th international Conference IAQVEC 2019: Indoor Air Qualy, Ventilation and Energy Conservation in Buildings. 5-7 September 2019, Bari, Italy

Impacts of energy retrofits on IAQ were studied in two European countries, Finland and Lithuania. Air change rates were estimated based on air flows measured through ventilation outlets and 24-hour monitoring of CO2 concentrations before and after various energy retrofits in multi-family buildings. The air change rates (ACR) after retrofits were higher in apartments with mechanical ventilation in Finland. The ACR after retrofits were smaller in all study groups in Lithuania, yet noticeably smaller in apartments with mixed ventilation. CO2 concentrations in all study groups in Finland were lower than in Lithuania. Also, some decrease in CO2 concentrations was noticed after retrofits in Finland, whereas an opposite trend was observed in Lithuania. In conclusion, impacts of energy retrofits were mainly marginally positive in Finland and mainly negative in Lithuania. Positive impacts were typically noticed in apartments with mechanical ventilation and "good" IAQ before retrofits. On contrary, negative impacts were noticed in apartments with natural ventilation and "adequate" IAQ. It was concluded that IAQ should be assessed before and after retrofits.publishedVersionPeer reviewe

Exposure to Second-hand tobacco smoke and health impact assessment of consumption transition from conventional cigarettes to new nicotine containing devices

The use of novel nicotine-containing devices as an alternative to conventional cigarettes is increasing rapidly. This raises many questions on the potential effects of this transition to both mainstream smokers and bystanders. The aim of this study was to investigate dynamics of aerosol generated by use of different nicotine containing products. The findings of this study will provide new evidence to scientists, health care professionals, and smokers that may help differentiate among the different alternatives. The laboratory simulation of the dispersion of exhaled tobacco products aerosol was conducted in an indoor chamber with controlled environmental conditions

Effects on energy retrofits on indoor air quality in three northern European countries

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Analysis of hygrothermal parameters in Finnish and Lithuanian multi-family buildings before and after energy retrofits

This study focuses on analyzing temperature- and moisture-related parameters based on data from 45 Finnish and 20 Lithuanian multi-family buildings. The data consist of two rounds of 2-month data-logging (1-h interval) of indoor temperature and relative humidity at two locations: one representing average occupied zone and the other one nearby the coldest spot of the building envelope. Between the two rounds of data-logging, 37 buildings from Finland and 15 buildings from Lithuania underwent retrofits, aiming to improve their energy efficiency. Measurement data were coupled with outdoor data from national weather stations, based on which a temperature factor (fc) and excess indoor moisture content (Δv) were calculated. Based on the results, fc was significantly higher in Lithuanian case buildings after the retrofits, whereas no significant differences were observed in Finnish buildings. In addition, Δv was significantly lower in Finnish case buildings after retrofits, whereas an opposite trend was seen in the Lithuanian buildings.acceptedVersionPeer reviewe