The expertise ordered by APVA confirmed that fresh air circulation must be ensured when renovating a residential building

The energy audit of 15 modernized apartment buildings in Lithuania, which was ordered by the Environmental Project Management Agency (APMA), revealed that in modernized buildings it is extremely important to ensure proper building ventilation.

“Every year, we conduct such audits in order to find out whether all the applied measures are effective and of high quality – for us, it is important not only to take care of the renovation of the houses, but also to make sure that everything in them is good after the work done. This year, according to the established criteria, we selected 15 apartment buildings from different cities of the country, these were buildings from Alytus, Biržai, Panevėžys, Priene, Ukmergė and Šilalė. They were built between 1960 and 1992, and the number of apartments varied between 24 and 100.

After the renovation, these apartment buildings reached B (6) and C (9) energy efficiency classes, 11 out of 15 buildings’ external walls were insulated with mineral wool insulation, other alternatives were polystyrene foam or polyurethane foam insulation panels,” says APVA’s Department of Energy Conservation of Buildings Edvardas Petrauskas, adviser of the department of implementation and maintenance of energy saving projects in buildings.

The analysis was performed at the beginning of the heating season in buildings that were renovated no earlier than two years ago. This was aimed at objectively evaluating the functioning of the heating system.

“During the inspection, an energy audit of the house was performed, the technical projects and the quality of the implemented solutions were assessed, that is, the quality of the works and the construction materials used. In general, we consider the results of the inspection to be good – in terms of energy saving, the thermal modernization works were carried out with high quality”, says the interviewer and adds that the inspection showed that the real energy consumption of the apartments is about 80 kWh per square meter. m, which is a very good achievement.

“During the examination of the implemented measures, it became clear that the greatest heat losses after the renovation of the apartment building are caused by the ventilation of the building – infiltration, natural and mechanical ventilation. Compared to the heat losses of the entire building, they averaged 50 percent. For comparison, in non-renovated apartment buildings, ventilation losses usually amount to 15-25 percent. all heat losses of the thermal building. However, after renovating the building, the heat losses experienced through leaky walls, roof, windows, etc. are reduced, thus the percentage of ventilation losses increases, so residents planning renovations should consider and choose to install mechanical ventilation devices with heat recovery,” says E. Petrauskas.

Proper ventilation can prevent health problems

Good ventilation of the building ensures fresh and fresh air and maintains a suitable microclimate in the room. In order to achieve this, it is most efficient to install a recovery system in the building.

“The microclimate in the apartment is highly dependent on ventilation, so residents who have installed a recuperation system have no problems with it. If this system is not available, residents should learn how to properly ventilate the apartment so that the microclimate in it is suitable for health”, says E. Petrauskas.

It is worth noting that dry indoor air can cause various health problems: irritation of the throat and eyes, especially for those who wear contact lenses, dryness of the skin of the face and hands, and if the protective layer is damaged, it can crack, and dry air irritates the mucous membrane of the respiratory tract, therefore, immunity may weaken, colds and other diseases may occur.

The simplest way to reduce indoor air dryness is to use air humidifiers. However, in renovated buildings in the cold season, due to excessive humidity, favorable conditions for the appearance of mold are created, so it is necessary to use them carefully.

“We are glad that neither mold nor excess moisture was detected in any apartment building during this study”, notes E. Petrauskas.

Residents can familiarize themselves with the audit findings and other relevant information about the renovation of the apartment building on the APVA website www.modernizuok.apva.lt

Author of the article: Kotryna Grušauskaitė

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