Standard-compliant ventilation concept

Due to the tighter construction method and changed ways of living different and higher requirements for home ventilation are being defined. The improved building shell of today’s new buildings allow little "natural" air change. The same also applies to energy-efficiently redeveloped buildings, e.g. after the exchange of windows. Thus, air moisture inside the rooms increases, so that mould formation can be observed to an increasing degree. The inadequate air change deteriorates the room climate, which can also affect the health and well-being of the tenants adversely. Furthermore, it is possible that a sufficient fresh air supply for gas hot water heaters or wood-burning stoves can no longer be ensured.

Consequently, a more intensive ventilation becomes necessary. However, simply opening a window is no longer an easy task. For this reason, standards now require an user-independent air change. The relevant regulations are as follows:

  • German EnEV (Energy-Saving Regulation)
  • DIN 1946-6: German home ventilation standard
  • DIN 18017-3: ventilation of bathrooms without outside window
  • DVGW-TRGI technical regulations for gas installations (combustion air supply)

Expert’s advice ventilation planning

The German home ventilation standard DIN 1946-6 is the most relevant regulation for planning the ventilation of domestic construction and prescribes the creation of a ventilation concept. Thus, planners and window manufacturers are responsible for providing extensive explanations and advice to clients.

expert's advice ventilation concept with arimeo window rebate ventsOver the past 20 years, we, the team of INNOPERFORM®, have supplied several million window rebate vents to our clients and supported thousands of objects during the planning stage in line with ventilation standard DIN 1946-6. Advice and support for the creation of ventilation concepts are services that we take for granted and that we provide free of charge. We are happy to calculate the dimensioning of arimeo for you, i.e. we help you determine how many arimeo will be required to satisfy the standards. By phone, e-mail or in person, the experts at INNOPERFORM® will look after your needs and work with you, if requested, to create customized solutions.

Planning tool – ventilation concept

For planning projects with cross ventilation, planners and window manufacturers are welcome to use our free calculation tool in the secure customer area of our website in order to define and calculate the number of arimeo required by current standards. Thereafter, you can integrate these calculation results in your ventilation concept according to DIN 1946-6.

German Energy-Saving Regulation: EnEV

The EnEV is the regulation defining the compliance with minimum air change. The exact air change rate for residential buildings is specified in DIN 1946-6. Sect. 6, para. 1 of the EnEV relates to the impermeability of the building shell and requires for buildings that,

„…the heat-transferring surrounding surface including joints is sealed air-impermeably and permanently in accordance with the generally accepted codes of practices.“

This tight construction has, in practice, increasingly led to higher air moisture in buildings and rooms which may result in the mould formation. Hence, sect. 6, para. 2 of the EnEV stipulates the requirement to comply with

„…the minimum air change required for the purposes of health and heating…“.

These requirements combined seem to be paradoxical; however, as a result of today’s construction methods, they are fully legitimately. The air change, which formerly came in through leakages in the building shell uncontrolled and thus, decreased air moisture, is not existing in tight buildings. In order to bring up the interior climate to a pleasant mould-preventing level again, controlled outer air transfer devices are required now. With them, it can exactly be determined how much air and most important where the air flows in.

German ventilation standard: DIN 1946-6

The required minimum air change is described and defined in the German standard DIN 1946-6 (home ventilation). A ventilation concept is now required for:

  • new buildings
  • refurbishments of apartment buildings at which more than 1/3 of the windows are replaced and
  • refurbishments of single-family homes in which more than 1/3 of the windows are replaced or more than 1/3 of the roof surface is sealed

In accordance with DIN 1946-6 a ventilation measure is required if the air flow rate, which comes in through leakages of the building shell (infiltration), is insufficient for an adequate ventilation, which prevents moisture formation. Assumptions are made in the DIN 1946-6 regarding the leakages. If a ventilation measure is required, at least the moisture proofing ventilation must be ensured user-independently. To reduce manual window opening, this minimum requirement can be exceeded optionally by planning higher user-independent ventilation levels.

Outer air transfer device in accordance with DIN 1946-6

arimeo can be used as an outer air transfer device in accordance with DIN 1946-6. Thanks to its sensitive air flow control, it is a self-adjusting outer air transfer device as defined in the standard. Our experts support you in calculating the number of arimeo required.

arimeo can be used in cross ventilation and as air supply for fan-assisted and shaft ventilation.

arimeo window rebate vents in cross ventilation arimeo window rebate vents in shaft ventilation arimeo window rebate vents in fan-assisted ventilation

Ventilation of bathrooms: DIN 18017-3

In accordance with DIN 18017-3, an exhaust air system is required for bathrooms and toilet rooms without a window. The ventilators can be switched in different ways. In standard cases, an exhaust air flow rate of 40 m³/h or 60 m³/h is required for an internal bathroom.

The same volume of fresh air now needs to flow in again. Part of this is generated by the building shell’s leakages, known as infiltration. The German standard DIN 18017-3 takes this into account and makes unit-dependent assumptions concerning its rate. In case of tight buildings, the infiltration available is usually insufficient to supply the ventilator with fresh air. The missing air quantity can be supplied by arimeo.


Important fact: according to DIN 1946-6 again, the nominal ventilation does not need to be calculated if the ventilator is being operated permanently and is used primarily to ventilate a bathroom or similar. It is sufficient to calculate for moisture proofing ventilation if it can be ensured that the air is equally distributed in all rooms.

Combustion air supply: DVGW-TRGI

Room air-dependent fireplaces, wood-burning stoves and gas hot water heaters require an adequate supply of air from the living space. For that purpose, fresh air needs to be able to enter the room from outside. The incoming air ensures adequate combustion (prevents the formation of carbon monoxide) and also ensures the eduction of exhaust gases by avoiding a critical vacuum in the room in which the device is installed. An adequate combustion air supply is therefore required by law. The volume of combustion air required was so far described in the German standard firing regulation (MFeuV) and its underlying technical regulations. In the future, the MFeuV does not state the combustion air volume required and the possibilities of air supply into the inside of a flat anymore. The calculational evidences are described now in the respective technical regulations exclusively. To be specific: for gas hot water heaters it is the DVGW-TRGI (technical regulations for gas installations) and for fireplaces and wood-burning stoves it is the TR-OL (technical regulation of the stove and air heating trade) as well as the German standard DIN 19896 (fireplaces for solid fuel – technical regulation for the installation, requirements for the instruction manual).

As a result of the increasingly well-sealed building shells, the combustion air supply and forced ventilation for room air-dependent fireplaces are becoming a major challenge. Formerly you have been on the safe side with the 4 to 1 rule of thumb, but nowadays the outside air flowing in through leakages does often no longer ensure a sufficient combustion air supply for fireplaces. Unpopular measures (e.g. shortening door leaves, ventilation grilles, unattractive openings in the building shell, removing gaskets of interior doors ) are frequently the order of the day after a window replacement.

The solution of these problems are arimeo window rebate vents, which are permissible outer air transfer devices as defined by the DVGW-TRGI. The air passing value at 4 Pa is known and has been confirmed by tests at the ift Rosenheim. arimeo increases the air yield within the combustion air network, since it allows additional outside air to flow in through the building shell.

The INNOPERFORM® air flow gasket (USD) for interior doors extends the efficiency of the combustion air network, hence increases the air yield for fireplaces – tested by TÜV. More information about the air flow gasket can be reviewed on our website.