May 24, 2017 - Building
While the general public admires magnificent new constructions, like the Elbphilharmonie in Hamburg, professionals know that renovation is the most rigorous discipline in the building sector. On the one hand, the new technology must bend to existing circumstances; on the other, the same demands for quality – in user comfort and sustainability – apply equally to new constructions and renovations. If there are restrictions, these often function to maintain the valuable building fabric – which is potentially under monument protection – or they arise from building codes. The effects can include the colorof the facade, permissible window designs, and what type of roofing tiles must be used. These also lead to limitations in building technology: concealed wiring is not permitted if the walls are made from sand stone; fire protection regulations prohibit laying cables in hallways. In cases like these, a careful eye and a wealth of ideas can find solutions that do justice to the building, its location, and the demands of the users. If conventional wiring is not possible, then radio-based data transmission – for example, using EnOcean – presents an alternative.
Downtown locations, proximity to the subway system, a direct view of the city park, a stone’s throw to the train station, or surrounding residential buildings also complicate issues. When large, 12-ton trucks have to navigate old city streets at a crawl to the building site, if delivery times are restricted in the pedestrian zone, or noise rules reduce the time frame for loud activities, these can add up to substantial limitations. The same restrictions apply if the building is not completely untenanted, where individual areas are still in use. Tenant changeovers often present the only chance to modernize buildings – visually as well as technically. This type of opportune approach is standard, yet it also is fraught with new challenges at the technical level.
In the case of automating the lighting, sun protection, heating, air conditioning and ventilation systems, partial renovations initially result in island solutions for individual floors or building sectors. “Merging these islands later often requires expensive changes to the wiring and programming,” states Martin Hardenfels, who, as Manager of Project Sales at WAGO, is in a knowledgeable position. It is substantially easier to reconcile these segments if the system behind them functions across building trades and offers pre-programmed functions for the controllers. Electrical installations become more flexible and can be adapted relatively quickly during renovations if they are equipped with pluggable wiring. “When systems like this operate, then the individual units function autonomously for their areas of responsibility. Additional segments can be connected later on an as-needed basis. All the data points are already available in the system,” explains Hardenfels. This also has advantages for maintenance and operation, because if a renter desires modifications, then the operator does not have to take the entire system off line, but instead can carry out localized changes.
High Time Pressure for Renovations during Operations
Often, renovations or conversions of the building technology are necessary when operations cannot, or should not, be completely shut down. One example is the Zinser fashion house in Tübingen in Baden-Württemberg. Renovations by floor were carried out at the end of 2015, and had to be implemented quickly. The time pressure applied through all project phases, ultimately affecting the installation of the new lighting technology. To comply with the narrow time frame, the leading installation company relied on the WINSTA® pluggable connection system from WAGO. Instead of individually wiring 2000 lights per floor, only 30 to 35 subdistributors had to be installed in each story.
When the control technology in the VELTINS Arena in Gelsenkirchen was replaced at the end of 2016, those responsible found an ingenious, if unconventional, approach to the time constraints. In order to quickly implement the renovations with the fewest limitations for the stadium users, the experts at ROM Technology from Düsseldorf pre-assembled the control components, equipped them with pluggable connectors and adapter circuit boards, installed the software, and tested the inputs. This substantially reduced the time required for installation on site. In addition, they created an intelligent fall-back potential, so that the experts could reestablish the old status at any time. This possibility is not usually possible in the case of substantial modernizations.
Desired Features: Versatility and Flexibility
Planners and skilled trade workers often confront additional obstacles linked to the building technology. Space in the switch cabinet is fixed, and rather limited, which presents difficulties in incorporating control and monitoring components in locations that previously used little or no automation. The new technology must also be able to link in older sensors and monitors – like temperature sensors that do not provide standardized digital or analog values, but instead a manufacturer-specific signal. In addition, LON®, KNX, or M-Bus networks are often present, which either should or must be incorporated. To even begin to offer functional and reliable building automation, control systems are required that can be flexibly integrated into existing infrastructures.
This is exactly the challenge that Ecotec, an engineering consulting firm from Bremen, faced when they decided in 2015 to refresh the controllers in the ICA technology in five office and administration buildings, in which Ecotec also rents space. For CEO Matthias Limberg, it quickly became apparent that the existing controllers would not be used again.
“The manufacturer’s projections exhausted our entire budget,” he reports with a wink. As all other field devices and sensors would be retained, the new technology would have to command a large number of interfaces. Surprisingly, space was not an issue: the previous system was so expansive that an average of one in every three switch cabinets was no longer required for the new ICA technology, which brought with it significantly increased functionality. For technical building equipment designers like Limberg, working on one’s own space offered an opportunity to work in an unusual fashion – without any time pressure at all. “The head electricians and I examined all of the control and monitoring functions. Including those that hadn’t been used in years,” he reports. In their stead, numerous new functions were integrated, including those promoting energy savings and smart metering. Even though the conversions are not yet complete, Limberg has a positive outlook, “This provided us with hours of fun!” This example also demonstrates that a proper inventory and critical analysis of the existing systems should be included to successfully renovate building technologies.
There are approximately 20 million extant buildings in Germany alone, including 1.5 million non-residential structures. The majority were constructed before 1979, thus prior to Germany’s first Thermal Insulation Act. As a consequences, real estate properties, particularly those built in the 60s and 70s, and true energy hogs. However, it doesn’t look much better abroad. According to the EU Commission, approximately 75% of existing buildings are energy inefficient, which means that the building sector accounts for around 40% of the total primary energy consumption in Europe. Office and management buildings, production facilities and warehouses, hospitals, and schools generally perform just as miserably as residential buildings. These efficiencies can be substantially increased through the use of modern building technology and operational optimizations – by around 30% to 50% according to the VDMA (Mechanical Engineering Industry Association). However, the rate of renovations in the EU is merely 0.4% to 1.2% per year, depending on the member state.
The possibilities concealed with existing buildings affect more than energy savings: the around 1.5 million non-residential buildings in Germany offer 2.2 billion m2 of usable space. These buildings are often located in areas that are now subject to different urban planning regulations than when they were built. For example, a limitation on structural height can lead to fewer floors in a new construction at the same location. The existing building, however, can retain its current height. A renovation, even under the most difficult technical requirements, that retains this economically valuable floor space, can be profitably exploited.
Last but not least, there are also financial incentives for renovation. These include those that also bring in numerous funding programs from the EU, the federal and state governments. These political incentives are equally available for homeowners, real estate managers of municipal properties, and owners of commercial properties, who engage in a renovation effort. Anyone who works with these funds quickly recognizes that bundling several measures makes sense. The scope of the subsidies or repayments is dependent on which combination of technical measures make the most sense. It is possible that the installation of a new ventilation system provides an opportunity to insulate the old ventilation shafts, or that replacing lights can be supplemented with presence and/or brightness sensors. Sometimes these supplemental steps are, in fact, required: when renovating ventilation systems, for example, retrofitting the frequency converters to stepless monitoring of the existing motors is mandatory to receive the subsidy.
Identifying Suitable Measures
Yet how do owners know which specific potentials are concealed in their real estate? There are several established, targeted approaches for energy auditing. One is certification as per the “eu.bac. System.” This certification was initiated in 2013 to ensure comprehensive incorporation of building technology and building automation within the framework of systematic evaluations. The standardized method is based on scientifically proven data and the relevant European standard, DIN EN 15232. Property managers profit from this evaluation because they also obtain information about potential improvements.
“One can only advise all building managers to have their systems analyzed according to eu.bac to uncover weak points and discover improvements,” advises Dr. Peter Hug, CEO of eu.bac, who spoke in an interview at the Forum on Building Technology at the VDMA (see page 28). WAGO became a “eu.bac System” partner in 2015, and seven colleagues from Project Sales have been trained as auditors. Over the course of an audit, they help to create transparency and provide operators with comprehensive information about the automation technology used in their buildings. This enables the group’s members to collaborate with building operators or service providers to create procedures for constructing new buildings or for renovating existing units.
Text: Julia Ockenga I WAGO
Photo: Lorenzo de Nobili, Till Werhan I Bildschön, ©iStock.com