Renovate faster and more affordably

Energiesprong-Living Lab Mönchengladbach (Germany)

On the road to a climate-neutral building stock, Germany is in a traffic jam. Progress is far too slow, especially when it comes to the energy-efficient renovation of existing residential buildings. Serial renovation with prefabricated building envelopes and standardized processes promises a quick and affordable solution. In Mönchengladbach, Am Brandhügel, five serial approaches to renovation were tested and implemented in a real-life test environment in a residential area. The company ecoworks participated with newly developed facade elements, including an integrated TGA module and wirelessly controlled Warema blinds.

To meet the climate goals of the EU Green Deal, the housing stock must also gradually become climate neutral. However, the necessary renovation rate of two percent has not yet been achieved in Germany and is currently stagnating at 0.7 percent. The housing industry in Germany attributes this mainly to excessively high investment costs, a lack of skilled labor and complex planning.

The energy leap for the heating transition

An alternative to the conventional renovation method comes from the Netherlands. It is based on series production technology and promises fast and cost-effective realization and solutions. The Energiesprong idea has been further developed for the German market by the former start-up ecoworks since 2019. The company ecoworks combines the standardization of processes for digitized planning, production and implementation with the industrial prefabrication of facade and (PV) roof elements.

The goal of ecoworks is to transform the renovated buildings to an energy-efficient NetZero house standard (= energy-neutral house). This refers to a balanced annual balance of energy production and consumption during the use phase. This goal was also realized in Mönchengladbach: In the residential area Am Brandhügel, ecoworks transformed five residential buildings with 20 residential units into energy-plus homes that meet the NetZero standard.

Renovation for "worst-performing buildings"

The demand is enormous: 71 percent of the more than 18 million residential buildings to be renovated were built before the first Thermal Insulation Ordinance of 1979 and have very high consumption values. Apartment buildings from the 1950s to 1970s, with their poorly insulated building envelope and simple cube shape, are particularly suitable for serial renovation. The renovation specialist ecoworks sees itself as a "partner to the housing industry for affordable energy-efficient renovations," explains Emanuel Heisenberg, founder and CEO of ecoworks. "As a general contractor, we support housing associations, from small cooperatives to housing groups, from initial assessment to serial implementation. We have now completed several projects and another 20 are in the planning or realization phase." The company promises economical and fast renovation at a fixed price. Completed projects have shown that construction time can be reduced to a few weeks and minimally invasive interventions in the living space. The realization can be carried out in occupied condition.

Innovation in the living lab

In Mönchengladbach, LEG Immobilien SE set up the first Energiesprong real estate laboratory in Germany to test serial renovations during ongoing work with different construction partners. In the LEG residential area Am Brandhügel, ecoworks was responsible for the renovation of five apartment buildings with a total of 20 residential units and 1,086 square meters of living space. These houses have two floors, typical of the 1956 construction year. Two entrances to two buildings with 4 flats each were combined into one block.

A 3D laser scan served as the basis for ecoworks to create a BIM model, which, as a digital twin, formed the basis for the fully digitized planning, from the initial idea to the millimeter-precise production preparation for robot-controlled prefabrication in the factory hall. With the serial renovation, the company is shifting 80 percent of the added value from the construction site to the factory.

Every house with a new shell

The residential houses in Mönchengladbach obtained from ecoworks a completely redesigned building envelope of ready-to-install facade and roof elements. The gray façade modules are clad with fiber cement boards in a wood look and insulated with cellulose or wood fiber. The windows, including blinds, and the supply lines for the living space ventilation and energy supply are already integrated into the module. After removing the old roofing, the roof received a new skin of insulated roof elements with profiled sheet metal cladding and photovoltaic modules.

The new shell could be installed in a very short time and the interventions in the flats were minimal. The old windows were removed and the window frames were covered with a new roof frame. In addition, the basement ceiling was insulated with mineral wool and a new heating system with heat pump and buffer tank was installed in each house. The heat supply was thus completely decoupled from fossil fuels. After the renovation, the buildings made a huge leap in energy efficiency from building class H to A+. The energy requirement improved from 292 to 22 kWh/m²a, supplied by the PV system on the roof. In terms of CO2 balance, 2.7 tons were saved over the life of the building.

With sun protection fit for the future

In view of the increasing heat stress in summer, effective shading is essential for living spaces. The new windows for the residential units in Mönchengladbach were therefore factory-equipped with a total of 100 WMS-controlled shutters from Warema, whose automatic control based on weather conditions enables energy-efficient use. The external blinds ensure sufficient living comfort even during heat periods, which will become more frequent and longer in the future, and avoid the energy-intensive use of air conditioning systems. In winter, the shutters support the energy performance of the new facade: the layer of air between the lowered armor and the windows helps keep the heat in the rooms.

Warema's prefabricated roller shutters are ideal for series production and enable efficient installation in the facade, as they are already completely pre-assembled. The WMS wireless control supports the principle of renovation from the outside: for the project in Mönchengladbach, the connection lines were laid on the old existing facade and are located in the insulation layer after the facade elements are installed. This product choice enables quick and easy integration into the construction process: The work can be carried out from the outside, so there is no need to enter the flats.

Warema - Partner for serial construction

Warema and ecoworks are linked by a forward-looking strategic partnership, because the demand for climate-neutral renovation is enormous and requires joined forces. The extensive, innovative portfolio, broad expertise in the field of solar shading and the excellent service network make Warema an efficient partner for modular construction - from the planning to the after-sales phase. Against this background, Warema, as a shareholder in ecoworks, sees its function as much more than that of a system supplier. "We want to revolutionize the housing and construction industry through serial energy-efficient renovations. Strong strategic partnerships with innovative companies like Warema are essential for this. We benefit both from Warema's long-standing expertise and its high-quality products," explained Emanuel Heisenberg of ecoworks.

Building sign

Project: Reallabor netZero-Sanierung
Location: Am Brandhügel 33-39, 41169 Mönchengladbach-Hardt, Germany
Usage: Living
Client: LEG Immobilien SE
Main contractor: ecoworks GmbH, Berlin
Building class: 3
Full floors: 2
Housing units: 20
Living area: 1.086 m²
Year built: 1956
Completion: 2023
Construction time: Renovation period 1 year
Products: Preconstruction roller shutters V4, new construction roller shutter NA-RO with aluminum profile A37, wireless control WMS