Serial refurbishment with ventilation
The building envelope of the future
The building sector is one of the biggest CO₂ polluters in Germany. The need for refurbishment in Germany is immense: the majority of buildings are significantly older than 50 years and therefore do not meet current energy standards. New, efficient solutions – innovative, functional and affordable – are needed to achieve climate targets and create affordable living space. One solution: serial refurbishment! In the following guide, we explain why this refurbishment concept can revolutionise the entire sector and why ventilation plays a crucial role.
What is serial refurbishment?
Serial refurbishment is an energy-efficient modernization concept based on digital planning and automated prefabrication of modular façade elements that are attached to the existing building envelope. A comprehensive analysis of the façade is carried out in advance using a 3D scan and AI image recognition. The individual modules, consisting of insulation, windows and thermal insulation, are then prefabricated in the factory. The heating, water pipes and electrics can also be integrated into the new façade.
A decisive advantage: energy-efficient ventilation systems can also be retrofitted as part of the serial refurbishment.
How does serial refurbishment work?Step by step to a modern building stock
3D scan
A digital twin of the building is created in advance using state-of-the-art technology.
Manufacturing
The façade elements are created in the factory on the basis of the analysis data.
On-site installation
The modules are fitted to the existing building envelope with little effort.
The advantages of serial refurbishmentWhy the concept can revolutionize the housing market
Shorter construction time
Around 80 % of the work is carried out in the factory - the high degree of prefabrication saves time on the construction site.
Sustainable
The ecological building materials and low energy consumption drastically reduce the buildings' greenhouse gas emissions.
Reducing costs
Thanks to the low operating and maintenance costs, the refurbishment method creates affordable living space.
Efficient
Standardized processes and modular construction lead to economies of scale - especially for similar building types.
Tenant-friendly
The residents can continue to live at home during the serial refurbishment.
Customized
No off-the-peg look - the façade of the building can be customized in the factory for each project.
Ventilation for serial refurbishmentThe new iV-Zero Prefab from inVENTer
In the course of serial refurbishment, the building envelope is heavily insulated and therefore increasingly sealed. Even if this initially appears to save energy, it also harbors risks. Without adequate air exchange, there is a risk of immense damage caused by mold in the home, and the indoor air quality of the residents also suffers. Energy-efficient ventilation systems continuously provide fresh air and at the same time use the heat from the exhaust air to warm up the fresh supply air. Around 90 % of the heat can therefore be retained with low energy consumption. The innovative Prefab design enables simple integration into the façade – with an internal air outlet in the window reveal. This clever corner solution ensures maximum design freedom and a discreet appearance.
The advantages of ventilation in serial refurbishment ...
One special ventilation solution
Energy saving
Continuous air exchange
State subsidies
First serial refurbishment in Saxony-Anhalt!
In 2024, inVENTer, together with TAG Immobilien GmbH and Ecoworks, celebrated the first serial refurbishment project in Saxony-Anhalt. Further refurbishments of this type are already underway in Wiesbaden, Hattingen and Mönchengladbach.
What does a serial refurbishment cost?Planning, investments & promotion
The high degree of prefabrication in a serial refurbishment initially requires detailed planning and major initial investment. In the long term, however, this approach proves to be cost-effective: the decisive efficiency advantages are particularly evident during on-site installation. The prefabricated façade elements can be installed in a short time without scaffolding – with an installation rate of up to 12 elements per day. This reduces the number of personnel required and considerably simplifies construction site logistics. The more projects are implemented in series, the greater the economies of scale – a clear advantage for future projects. Added to this are significantly reduced energy consumption and a more durable building envelope.
Builders can significantly reduce costs anyway with federal subsidies. The KfW grants low-interest loans of up to €150,000 per residential unit. As part of the BEG’s KfW 261 funding program, up to 25% of the costs can also be credited as a repayment subsidy (if an efficiency house level of 40EE is achieved). In addition, 15% special bonus for serial refurbishment and 10% extra bonus through the Worst-Performing-Building (WPB) are possible – up to a maximum subsidy. In total, this results in a maximum repayment subsidy in the KfW program of 45%.
A major advantage of the promotion: the repayment grant does not only apply to the serial refurbishment of the façade, but to all eligible measures – e.g. roof, windows, doors or heating.
The application for the KfW loan must be submitted before the refurbishment measures are commissioned or financing agreements are signed. A prerequisite for the funding is also a GEG certificate from an energy efficiency expert confirming the planned efficiency house level. Current information on the subsidies for serial refurbishment can be found here..
ConclusionThis is why serial refurbishment is the method of the future
Serial refurbishment is a forward-looking solution for efficiently, sustainably and economically tackling the enormous need for refurbishment in the German building stock. A high degree of prefabrication, short construction times and standardized processes mean that considerable efficiency and cost benefits can be achieved. At the same time, the method also enables the uncomplicated use of decentralized ventilation. Thanks to attractive funding opportunities, for example from KfW, serial refurbishment is also becoming increasingly financially attractive for building owners. This makes it a key building block on the way to a climate-friendly and affordable building stock of the future.
FAQ: Your questions about serial refurbishment
What is meant by serial refurbishment?
Serial refurbishment describes a modernization concept in which prefabricated facades are attached to existing buildings. These modules contain the insulation, windows and thermal insulation and can also integrate energy-efficient ventilation systems. Additional storeys, balconies and roofs can also be renovated to make them more energy-efficient.
When is a refurbishment considered “serial”?
In the case of serial refurbishment, at least 80% of the heat-transferring façade surface of the existing building to be refurbished must be completely refurbished with factory prefabricated façade elements. The prefabricated façade or roof elements must be able to be installed on site unchanged in size and shape. The height of the elements must be at least storey-high.
Is serial refurbishment suitable for all building types?
Serial refurbishment is always suitable when buildings have a rectangular floor plan with straight outer sides and a simple pitched roof – as is the case with classic prefabricated buildings. This means that around 30 % of all apartment buildings in Germany can be renovated using this approach. Whether single-family homes or multi-storey apartment buildings – serial refurbishment can be successfully implemented in many projects.
What are the advantages of serial refurbishment compared to traditional methods?
Serial refurbishment shortens construction times and contributes to climate protection through sustainable materials and energy efficiency. It reduces costs, enables efficient implementation in similar buildings and allows tenants to remain in their apartments during the work.
Are there state subsidies for serial refurbishment?
Yes, building owners can benefit from state subsidies for serial refurbishment. The KfW grants low-interest loans of up to €150,000 per residential unit and offers a repayment subsidy of up to 45% for all eligible measures, including façade renovation, as part of the KfW program 261.
Would you like to find out more?Get in touch with us!
Schnellkontakt