Whether in schools, daycare centres, offices, or commercial spaces – efficient and reliable ventilation is essential in modern buildings. Decentralized ventilation systems offer a flexible solution that performs well in both new construction and renovation projects. They ensure high indoor air quality, help reduce energy consumption, and can be individually adapted to the requirements of different rooms.
Briefly summarized: Decentralized Ventilation System
Decentralized ventilation systems are ventilation systems that operate independently in individual rooms of a building. In contrast to centralized systems, which require a duct network for air distribution, decentralized units function without ductwork and offer high flexibility during installation. They can be used efficiently in both new buildings and renovation projects and are particularly resource-efficient, as they require only minimal structural modifications. With integrated heat recovery, they contribute to energy efficiency and help reduce CO₂ emissions, making them a sustainable solution for modern buildings.
Where are decentralized ventilation systems used?
Decentralized ventilation systems are used in residential buildings as well as in offices, commercial properties, and educational institutions. While the requirements for decentralized systems in residential settings often differ in focus, this entry concentrates on their application in non-residential buildings. Key aspects include air quality in high-occupancy spaces, energy efficiency, and flexible maintenance.
Decentralized ventilation systems in schools and daycare centres
In educational settings such as schools and daycare centres, good indoor air quality is essential, not only for concentration and performance, but above all for health. Decentralized ventilation systems ensure continuous air exchange, reducing CO₂ levels and effectively removing aerosol particles that may contain viruses. This significantly lowers the risk of infection without the need to keep windows permanently open—an advantage that helps prevent energy losses and blocks out disruptive outdoor noise.
Findings from the OLiS research project: Optimizing mechanical ventilation concepts in schools
The OLiS research project (Optimizing mechanical air distribution concepts in schools) investigated the efficiency of mechanical ventilation systems with heat recovery in school buildings. The findings showed that such systems can reliably maintain indoor air quality while significantly reducing energy consumption compared to conventional window ventilation. Specifically, depending on the type of energy used, CO₂ emissions related to heating and ventilation in a classroom could be reduced by up to 75%. The use of mechanical ventilation systems combined with heat recovery can therefore make a substantial contribution to achieving climate-neutral school buildings.
Decentralized ventilation systems for offices and commercial buildings
In office buildings and commercial properties, decentralized ventilation systems help maintain a pleasant indoor climate that promotes both employee productivity and well-being. Since rooms such as meeting areas, open-plan offices, or workshops often have varying ventilation requirements, decentralized systems can be individually adjusted to meet the specific needs of each space. At the same time, they eliminate the need for complex duct networks, which can be impractical in environments with flexible room layouts or frequent spatial modifications.
What is a decentralized ventilation system?
A decentralized ventilation system is a type of ventilation setup in which individual units are installed directly in the rooms to be ventilated. These units operate independently, regulate the flow rate, provide fresh air to each room while simultaneously extracting stale air. Decentralized systems do not require complex ductwork and are highly flexible in terms of installation, making them suitable for both new buildings and renovation projects. Fan coils can also be used in this context and additionally offer the possibility of both cooling and heating.
What is the difference between centralized and decentralized ventilation?
The key difference between centralized and decentralized ventilation systems lies in the method of air distribution and installation. A centralized system uses a single central unit to supply fresh air to the entire building and extract used air through an extensive duct network. Such systems are particularly efficient in large buildings with uniform requirements for air quality and temperature. However, they require careful planning and adequate space for ducts, which makes them especially suitable for new construction projects.
In contrast, decentralized systems operate independently in individual rooms, without the need for ducts. They are flexible in use, particularly in existing buildings or structures with varying requirements across rooms. The units are typically installed directly into exterior walls, simplifying installation. However, larger buildings may require a greater number of units, which should be considered during planning.
How much maintenance is required for decentralized ventilation systems?
Whether a centralized or decentralized ventilation system is used has a direct impact on maintenance requirements. A key advantage of decentralized systems is that each unit can be serviced independently. This allows maintenance work to be distributed flexibly throughout the year, helping to avoid operational disruptions and ensuring smooth building operations.
Another benefit is the easy accessibility of the units, which significantly simplifies the maintenance process. Routine service tasks can often be carried out as part of standard facility management procedures. Since decentralized systems do not require ductwork, fire dampers, or special hygiene measures, maintenance is typically limited to filter replacement and basic functional checks—saving both time and costs.
Heat recovery: Focusing on energy efficiency
Decentralized ventilation systems extract stale air from the building while using heat recovery to preheat incoming fresh air. This prevents the interior from cooling down, which in turn reduces heating demand and improves overall energy efficiency. Such systems not only help lower operating costs, but also comply with the requirements of the German Energy Saving Ordinance (EnEV) and the Building Energy Act (GEG). Additionally, they may qualify for government incentive programs that support energy-efficient construction and renovation—making them a cost-effective and flexible solution, especially for retrofitting existing buildings.
Installation types of decentralized ventilation systems
Decentralized ventilation systems can be implemented in different installation configurations, depending on the structural conditions and specific requirements. Here are a few examples:
Ceiling-mounted unit
The nearly invisible ceiling unit is suitable for applications with floor-to-ceiling glazing and without a raised floor system. It can be combined with various ceiling elements, such as lighting units.
Wall-mounted unit / parapet-mounted unit
The parapet unit is ideal for cost-efficient renovation projects with limited floor-to-ceiling height, as it does not require raised floors, hollow floors, or suspended ceilings.
Floor-mounted unit
The floor unit is suitable for installation in raised or hollow floors due to its low installation height. It can be used in both renovation projects and new buildings with floor-to-ceiling glazing.
How much does it cost to install a decentralized ventilation system?
The cost of installing decentralized ventilation systems depends largely on whether the project involves new construction or renovation. In new buildings, the units can be integrated into the planning process from the beginning and installed without additional structural modifications. In renovation projects, the effort is greater, as existing building envelopes and room layouts must be taken into account. This may involve retrofitting wall penetrations for air intake and exhaust or adapting the electrical installation. Depending on the building’s condition, structural work such as core drilling may also be required to install the systems correctly. As a result, overall costs for renovation projects are generally significantly higher than for new construction.
Decentralized ventilation systems in practice
Decentralized ventilation systems are highly versatile and can be tailored to the specific needs of different building types and uses. Whether in schools, daycare centers, offices, or other non-residential buildings, selecting the right system depends on factors such as room size, frequency of use, and structural conditions. The following sections present two specifically optimized application areas: ventilation solutions for educational facilities and systems designed for office environments.
Optimal learning environment and maximum infection control: LTG ventilation units for schools
LTG’s Eco₂School ventilation units are specifically designed to provide a healthy and comfortable indoor climate in schools and daycare centres. They ensure an optimal learning environment and offer maximum infection control by supplying 100% fresh air. All relevant guidelines are met, including VDI 6022, VDI 6040, and the recommendations of the German Environment Agency (UBA).
Demand-controlled fresh air supply: Health and sustainability for office applications
For offices and commercial buildings, LTG offers ventilation systems that automatically detect the air demand in each room and mimic natural air movement. This enables a demand-driven and natural air supply, providing user-oriented, individual climate control—all through a single façade opening. This intelligent control system not only optimizes energy efficiency, but also creates a pleasant working environment and supports modern standards in sustainability and architecture.
Control intelligence for LTG decentralized ventilation systems
With our decentralized control intelligence, LTG units can be connected via manufacturer-independent bus systems. LTG Connected Intelligence® offers a cost-effective, simple, and flexible automation solution for LTG air-water systems. The system enables demand-driven, room-specific ventilation and air conditioning, with or without integration into a central building management system (BMS). We have deliberately opted for an open system architecture that is compatible with common bus protocols, making it easy to integrate sensors and actuators into the control system. This gives planners, investors, and users greater freedom and flexibility.
Building renovation: Benefits and objectives of decentralized ventilation systems
In the context of building renovation, decentralized ventilation systems offer notable sustainability advantages. Increasingly strict regulatory frameworks, such as the German Building Energy Act (GEG) and the goals of the European Green Deal, require a reduction in CO₂ emissions and a decrease in primary energy consumption in existing buildings. Decentralized ventilation systems provide an efficient solution, as they can be retrofitted easily—without major structural alterations or the installation of extensive ductwork. This minimizes renovation efforts while simultaneously conserving resources and saving energy through heat recovery and the elimination of complex piping systems. These systems thus contribute not only to achieving national climate goals, but also support the EU’s objective of climate neutrality by 2050 by enabling energy-efficient operation and the reduction of greenhouse gas emissions.