From 2021 in all European countries all new buildings (or parts of new buildings) will have to meet the requirements of energy performance class A++(information is taken from the EPBD – European Performance of Buildings Direction; Directive 2010/31/EU).


Engineering professionals who work in UAB Gildera are constantly improving their knowledge and seek that timber panel homes, which are manufactured in the company, would suit the highest requirements. Therefore, we suggest you to choose UAB Gildera prefabricated passive houses which meet the requirements of energy efficiency class A++.


A house (or part of a house), assigned to the energy performance class A++, is a building which almost do not use energy. In order to find out the best ways that help building A++ class passive panel houses, it is necessary to determine what the energy performance is. Based on information provided by the law, energy performance (of a house, or part of a house) is described as amount of energy, necessary when a building is used according to its intended purpose. The energy performance is calculated in accordance to the applicable requirements and expressed by the energy efficiency class marked as C index.

According to the data of energy performance, A++ class building has a C index equal to <0,25 (in comparison: C index of a B class house is equal to <1; A class C < 0,5; A+ class C < 0,375). One of the most significant parameter applied for the passive house is that the total amount of energy needed for a house during one year period cannot exceed 15KWh (in this way, passive house use a very small amount of energy). These spectacular results can be achieved while installing an effective thermal insulation and tightness system, using efficient mechanical ventilation system and making use of renewable energy sources.

Even though the initial building price of passive house can exceed the building price of houses which belong to the lower energy efficiency class, but the money that you invest into A++ house will soon pay off. Just imagine that majority of energy needed for A++ class passive prefabricated house is taken from renewable energy sources. Moreover, it is important to take into account the fact that while living in the passive house you can reduce the environmental pollution as well. According to the calculations, the average, traditional house emits about 6 kg of CO2 within one year period, while passive house can only emit about 2,1 kg of CO2.

It is possible to claim that common provisions of how to reach A or A+ energy efficiency class for a house can differ according to the particular continent or country. However, technical parameters of A and A+ class houses are strictly regulated in accordance with the requirements provided by German Passive House Institute.


1.Thermal properties of a house (or part of a house) – expressed by coefficients of thermal conductivity (coefficients are provided in m2K/W value).


Coefficients of thermal conductivity are one of the most important indicators, which show that building (or part of a building) is properly assigned to the class A or A+. All the calculations connected with thermal conductivity of a house are made by our engineering professionals.

2.Tightness (air exchange)

In order to comply with the requirements of A++ energy performance class, it is important to ensure that a house (or part of a house) would have a high-quality tightness system. If you provide a good tightness system you protect your new house not only against the loss of heat but also against humidity which can demolish various constructions which are not waterproof. House tightness system in passive house has to be even better than in houses of A or A+ class. For this reason, it is very important to tightly combine and seal separate building structures, minimize ‘cold bridges’ and select the most effective way to insulate the house. High-quality tightness system can not only protect a house from the heat loos but it also creates a comfortable and pleasant for living environment. In addition, a good tightness system can also reduce the noise. According to the calculations, sound level in houses which need a small amount of energy (class A, A+ and A++) is equal to 25 db (A).
The indicator which represents the level of air exchange in houses of A++ class (also A and A + classes) is equal to n50≤0,6 h-1.

3.Renewable energy sources

The use of renewable energy sources in A++ class houses is another good quality which distinguishes such type of houses from other more simple buildings. The most commonly used renewable energy sources are: wind power, solar power, aero thermal, hydrothermal and geothermal resources, biomass and biogas. The choice of different renewable energy sources depends on individual project, country, in which the house is going to be built, and local climate conditions.

4.Mechanical ventilation system

It is essential to install a high-performance mechanical ventilation system, which creates a comfortable and pleasant for living climate, in houses which require a very low amount of energy. One of the most important tasks for mechanical ventilation system is to properly use the air which flows in the house and outside of it. If mechanical ventilation system is properly installed, you can be sure that temperature in the house will stay the same. Moreover, high-quality mechanical ventilation system do not make any wind drafts and eliminate dust or any other small particles from the air which flows inside the house. For this reason, you can enjoy breathing fresh and clean air which flows all over the house.


Engineering professionals, who work in UAB Gildera, are constantly improving their knowledge to ensure that A++ class passive houses, which are produced in the company, would meet the highest requirements. So, choose our A++ prefabricated houses and enjoy not only the pleasant microclimate in your new house but also significantly reduced house maintenance costs.

Sales manager Inga –