Frequently Asked Questions

In the field of ventilation, energy recovery means recovering heat, ideally also moisture, from the exhaust air and then transferring the heat and moisture into the incoming fresh air, which is then distributed to the living space.

When we talk about natural ventilation, we mean ventilation primarily through windows.

Thus, all the ventilation of the space depends on the user.

It is a standardised calculation that gives a modelled total energy consumption of the house and also assesses the share of green energy sources in the total energy consumption.

In rooms with a need for impact ventilation, an exhaust fan is placed to create a negative pressure. This is then compensated by drawing in fresh air through dedicated openings (ventilation shafts), but often also through leaky areas of the building that are not designed for this purpose, for example through window frames (micro-ventilation), around window sills, goosenecks and other penetrations.

Under-pressure ventilation is a direct cause of mould, through the cooling and condensation of moisture in leaky areas of the building that are not designed for ventilation.

It is a non-toxic, colourless, tasteless and odourless gas that is heavier than air. CO2 is produced by the reaction of carbon with oxygen, for example in ordinary breathing. It is an easily measurable and accurate indicator of air quality.

It replaces natural ventilation by infiltration, which is not possible in well-insulated houses.

Sometimes the term controlled ventilation is also used.

The life-giving component of air, essential for the existence of most living organisms on this planet.

Is natural ventilation, where, especially in older houses, air flows in and out of the house through windows or door frames and through various leaks in the structure, whether intended or not.

In older houses, infiltration would provide more than half of the fresh air supply.

Means that its composition and the materials used in no way allow air moisture to penetrate.

Can not be considered a substitute for ventilation.

Composition and the materials used allow moisture to leave the perimeter wall always to the outside.

It is essential to prevent the penetration of air moisture from the interior into the building envelope.

It can not be considered a substitute for ventilation.

Is used to monitor the indoor air quality and to control ventilation systems according to the current level of air pollution.

The Blower-door test is a detection method to determine the airtightness of the building envelope and thus the energy performance of the house.

In the heat exchanger, the air coming from the outside is heated by the air that is exhausted from the interior.

Relative humidity is the ratio between the amount of water vapour in the air and the maximum possible amount of vapour that the air can hold. It is one of the parameters that significantly affects the quality of the indoor environment.

Is the heat gain from the exhaust air and the subsequent transfer of energy to the incoming fresh air.

In addition to warming the air coming into the interior, the enthalpic exchanger can also return a significant amount of humidity to the interior and thus optimise the relative humidity in the house or apartment.

In every air there is a certain % of water vapour. If the temperature drops below the so-called dew point, water vapour starts to condense. This is caused by a reduction of the volume of air into which the water can no longer fit.