Planning aids for decentralised ventilation systems: tools, software and calculation bases

Why sound planning is crucial

The planning of ventilation systems poses a particular challenge for architects, building services engineers, and installers. Decentralized ventilation requires detailed calculation of air exchange rates, optimized placement of ventilation units, and consideration of structural conditions. To ensure an energy-efficient and standard-compliant solution, well-founded calculations and planning aids are therefore indispensable.

What requirements must a good planning solution meet?

A high-quality planning tool should include the following functions:

• Compliance with standards: Ventilation planning must comply with regulations such as DIN 1946-6, EnEV, and GEG.
• Consideration of building characteristics: Room size, construction, insulation, and use play a decisive role.
• Volume flow calculation: The minimum air exchange rate as well as humidity and CO₂ levels must be calculated correctly.
• Integration of sound insulation values: Ventilation must not generate any sources of noise and must take sound insulation into account.
• Creation of documentation: A detailed planning aid should automatically generate reports and evidence for building owners and authorities.

Basics: How is decentralized ventilation calculated?

Standard-compliant ventilation planning requires a calculation of the air exchange per room to ensure sufficient moisture protection and air quality:

• Volume flow according to DIN 1946-6: This determines the necessary air exchange per hour (h-1).
• Calculate air exchange rate: Depending on room size, number of occupants, and use.
• Influence of window tightness: In modern buildings with a tight envelope, increased air exchange is required.
• Planning of airways: To avoid disruptive air currents, supply and exhaust airways must be optimally arranged.

Calculation basics for efficient ventilation systems

Efficient ventilation systems require precise calculation to function optimally. The basis for planning such a system lies in the careful evaluation of the individual requirements of the building and its use. By taking factors such as room size, air volume flow, and air quality into account, the most effective ventilation solution can be determined.

In the context of calculation bases, determining the air exchange rate plays a decisive role. This value indicates how often the air in a room is exchanged within an hour. This information can be used to determine the amount of air required for an optimal indoor climate.

Another important aspect in the calculation of efficient ventilation systems is the consideration of heat recovery. By using ventilation units with heat exchangers, a large part of the heat energy can be recovered from the exhaust air, resulting in significant energy savings.

The choice of suitable ventilation components, such as active fans with heat recovery or passive outside air vents, is based on the previously calculated parameters. The efficient planning of a ventilation system therefore requires a sound understanding of the calculation principles and a detailed analysis of the specific conditions on site.

By internalizing and applying the calculation principles for efficient ventilation systems, you can ensure that the air quality in buildings is maintained at an optimal level. Careful planning is the key to a healthy and comfortable indoor climate that also ensures energy efficiency.

Various planning aids for decentralized ventilation systems

When planning decentralized ventilation systems, there are a variety of tools that can support architects, engineers, and planners. These planning aids can be roughly divided into normative principles, software/simulation tools, tables and checklists, and integrative approaches such as CAD/BIM solutions. Below is an overview of the most important tools:

1. Normative principles and guidelines

• DIN and EN standards: Various standards are relevant for the planning of ventilation systems. For example, DIN EN 13141 (Ventilation and air conditioning – Measurement methods for determining ventilation rates) and DIN 1946-6 (Ventilation of residential buildings and buildings) specify important framework conditions. These standards define requirements for air exchange rates, filter performance, noise levels, and energy efficiency.
• VDI guidelines: VDI 6022, which deals with hygiene in ventilation and air conditioning systems, offers further recommendations, particularly with regard to the prevention of pollutant transfer and germ contamination.
• Energy saving regulations and subsidy programs: Current legal requirements (e.g., EnEV, GEG) and regional subsidy programs can also influence the design of decentralized ventilation systems. Planners should take these requirements into account in order to comply with both building regulations and energy requirements.

2. Software and simulation tools

• Simulation tools: Programs such as EnergyPlus, DesignBuilder, or similar software solutions can be used to perform detailed simulations to calculate air flows, thermal profiles, and energy consumption. These tools make it possible to compare different scenarios and optimize the design of the system.
• Manufacturer-specific planning tools: Many manufacturers of decentralized ventilation units offer their own online tools or Excel-based calculators that can be used to calculate the number of units, positioning, and dimensions relatively quickly based on specified parameters (e.g., room volume, air exchange rate, filter performance).
• CFD simulations: For complex issues (e.g., in buildings with unusual geometries or special usage concepts), computer-aided flow simulations (computational fluid dynamics, CFD) can help to analyze local air flows and any comfort issues (such as drafts or cold air zones) in detail.

3. Tables, checklists, and Excel tools

• Dimensioning tables: Tables with typical values (such as recommended air exchange rates, pressure losses in ducts, noise level ranges) support initial estimates and preliminary planning. They provide a quick overview of the requirements and enable initial comparisons between different design variants.
• Checklists: Standardized checklists help to systematically work through all relevant aspects—from compliance with normative requirements to sound insulation and integration into the overall system. This ensures that no important planning details are overlooked.
• Excel calculators: Excel tools created in-house or provided by manufacturers can be used to easily perform specific calculations, such as determining the required ventilation capacity or designing device groups.

4. CAD and BIM integrations

• CAD libraries and plugins: Modern planning tools make it possible to integrate ventilation components directly into CAD models. Manufacturers often offer libraries that can be imported into common CAD programs to achieve precise planning and visualization.
• BIM (Building Information Modeling): The integration of ventilation systems into a BIM model promotes interdisciplinary collaboration and enables the simulation of operating and maintenance processes as early as the planning phase. Centralized data exchange allows conflicts to be identified at an early stage and corrected accordingly.

5. Best practice guidelines and case studies

• Technical literature and guidelines: In addition to standards and technical manuals, there are numerous best practice guidelines that provide practical tips and empirical values for the planning of decentralized ventilation systems. Organizations such as the German Sustainable Building Council (DGNB) and the German Ventilation and Air Conditioning Technology Association (FDL) regularly publish guidelines and case studies.
• Empirical values from real projects: Case studies often provide valuable insight into practical implementation and can help identify typical problems and their solutions. These empirical values are often incorporated into the further development of planning aids and software tools.

The planning of decentralized ventilation systems requires an interdisciplinary approach that takes into account both normative requirements and practical circumstances. Various planning aids such as standards and guidelines, specialized software solutions, tables and checklists, and modern CAD/BIM integrations make it possible to plan and implement ventilation systems efficiently, in an energy-optimized and comfortable manner. Careful selection and application of these tools contributes significantly to the development of a holistically optimized building concept.

Advantages and possible applications of planning software

The use of planning software for decentralized ventilation systems offers a number of advantages. By using these specialized tools, TGA planners and architects can develop more efficient and precise ventilation concepts. The software supports the calculation and dimensioning of ventilation systems, which leads to optimized air quality in the rooms.

A major advantage of planning software is the time it saves. Complex calculations that used to have to be done manually are now performed automatically. This enables faster and more accurate planning of decentralized ventilation systems, allowing projects to be implemented more efficiently.

In addition, the software ideally enables better visualization of the planned ventilation systems. Building services engineers and architects can thus gain a realistic idea of how the system will function and how it can be integrated into the overall concept of the building as early as the planning stage.

Furthermore, the software can be used to run through various scenarios and find optimal solutions. Planning software makes it possible to adjust various parameters and thus determine the best possible configuration for the respective requirements.

How to choose the right planning tool – decision-making factors

The following criteria are crucial when selecting a suitable planning tool:

• Project size: Is the tool suitable for single-family homes or large residential complexes?
• New construction vs. renovation: Some software solutions are specifically optimized for renovation projects.
• Compatibility with existing software: Architecture and CAD programs should be able to be integrated.
• Automated documentation: A good planning tool automatically generates reports and documentation.

Ultimately, planning software and tools help to improve the quality, efficiency, and sustainability of ventilation systems. Through precise planning and calculation, building services engineers and architects can ensure that decentralized ventilation systems meet high standards of energy efficiency and comfort.

Tips for optimal use of planning aids

• Ventilation systems are crucial for many construction projects in order to ensure a comfortable indoor climate. When using planning aids, it is important to consider the specific requirements of the project.
• Start with a detailed analysis of the air flows and room sizes to determine the optimal ventilation systems.
• Use the planning software to simulate different scenarios and find the best solution for ventilation.
• When selecting ventilation systems, also consider external influences such as heat recovery and sound insulation.
• An important tip is to keep an eye on the user-friendliness of the planning aids in order to work efficiently.
• Be sure to offer regular training on the use of the planning software to your team in order to exploit its full potential.
• Ultimately, you should view the support tools as aids rather than rigid rules in order to maintain flexibility in planning.

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A thorough understanding of the planning and calculation of decentralized ventilation systems is crucial for the successful implementation of projects. The requirements for a good planning solution for efficient ventilation systems are high and require the use of suitable planning aids. By selecting the right tools and software, building services engineers and architects can find the optimal solution for their projects. The calculation bases for efficient ventilation should be carefully analyzed in order to fully exploit the advantages of a well-planned ventilation system. The variety of different planning aids offers numerous application possibilities and supports the implementation of individual ventilation concepts. Use the various tools and software to implement efficient and durable ventilation solutions and successfully complete projects. For individual advice or a specially tailored planning solution, please feel free to contact us directly!