Will sustainability be enshrined in building codes?

A striking example of this was created in recent years in Sydney, Australia. In the 1970s, the AMP Center—a 46-story skyscraper—was built in the central business district of this metropolis. Nearly 50 years later, plans were made for a new, modern building. Following a construction phase between 2018 and 2021, the Quay Quarter Tower now soars into the sky where the AMP Center once stood. Compared to its predecessor, the usable floor area has been doubled, and six additional floors have been added. So far, so unspectacular. But that changes when you take a closer look at the construction method: Only about one-third of the AMP Center was demolished; roughly 95 percent of the building’s core was preserved. The Quay Quarter Tower was built on this foundation—though “attached” might be a more accurate description. Today, the old AMP Center makes up about 75 percent of the Quay Quarter Tower, which appears to be a new building both inside and out. It becomes even more remarkable when you consider the staggering savings made possible by this approach instead of building from scratch: Construction costs equivalent to 80 million euros (24 percent of total construction costs), 12,000 metric tons of CO2, and a reduction in construction time of nine to twelve months. This achievement was rightly honored with the prestigious International Skyscraper Award 2022/23.

Given these figures, it is hardly surprising that the concept implemented in Sydney is currently inspiring imitators around the world. Sustainable construction is thus increasingly establishing itself as the “ideal model” among building methods. The focus is on environmental sustainability, social responsibility, and resource efficiency. A key element is the integration of environmentally friendly practices into the construction process. This takes many forms, such as reducing waste and emissions, using renewable energy during construction, or employing building materials that are already sustainable.

Political measures follow societal discussions and developments. The construction industry is no exception here. To use a metaphor, the path toward sustainable construction needs “guardrails” so that all stakeholders can travel along it quickly and safely. This is where building law comes into focus. To ensure it can fulfill its guiding role, lawmakers are called upon to incorporate sustainability and climate protection standards into the law. This calls for creativity, as there is a whole range of options available to promote sustainable construction. Meaningful incentives, the provision of attractive financing options, or the creation of special certification systems are just a few examples.

So far, lawmakers have made only very tentative use of these options. To stay with the metaphor: Anyone who embarks on the path of sustainable construction is often treading on uncharted ground. Recent changes to the 16 state building codes have focused primarily on digitalization. While the “solar mandate”—which varies significantly from state to state—is worth highlighting as a measure to promote greater sustainability in the construction industry, However, the example from Sydney illustrates that this is likely only a first step at best, and much potential currently remains untapped. The federal legislature, too, had set its sights high with the 2011 Climate Protection Amendment to the Federal Building Code (BauGB). Ultimately, however, it added only a few isolated regulations and requirements related to climate protection. A comprehensive overhaul of the BauGB geared toward the needs of sustainable construction failed to materialize. The European Parliament was at least able to agree on more concrete measures in December 2023. All EU member states have thus committed to achieving “climate neutrality” for their building stock by 2050 through national regulations. Although the first regulatory guidelines have been established, it remains to be seen what specific legislative changes will follow to achieve the targeted goals.

Yet there is plenty of room for success stories here in Germany. Currently, the building sector accounts for approximately 30 percent of nationwide CO2 emissions, and approximately 55 percent of all waste is generated during the construction and demolition of buildings. Consequently, there is a growing chorus of voices among experts who would like to see the principles behind the construction of the Quay Quarter Tower enshrined in German law as well. For example, the Federal Chamber of Architects recently called for a fundamental reform of German building law, which is currently primarily focused on the planning, construction, use, and demolition of buildings. The focus should be on further developing the Model Building Code—which serves as the basis for the 16 state building codes—into a “Renovation Code.” An even more far-reaching demand was made by the chambers of architects, environmental organizations, and private citizens in an open letter addressed to Federal Minister of Construction Klara Geywitz: a “demolition moratorium” is intended to create the legal framework for replacing demolition and new construction with the preservation, renovation, conversion, and expansion of the existing building stock. Here, too, the transformation of the Building Code into a “Renovation Code” is viewed as central.

From the perspective of those involved in construction, sustainable building means not only making the actual construction process environmentally friendly—for example, by using materials and technologies that ensure ecological and economic efficiency—but also focusing on the building’s future use as early as the planning phase. As is so often the case, general contractors play a crucial role in this regard. Their expertise and ability to manage and coordinate complex construction projects make it possible to design even large-scale projects in a sustainable manner. For example, existing warehouses or logistics centers offer the opportunity to repurpose them in a sustainable manner rather than demolishing and rebuilding them. Creative solutions such as adding stories, constructing extensions, or repurposing parts of buildings can significantly reduce resource consumption. By reusing building components, carrying out careful renovations, and improving energy efficiency, the ecological footprint can be minimized. 

As with any change, there are many hurdles to overcome on the path to a sustainable construction industry. Certainly, the higher costs associated with using sustainable building materials and technologies are among the most significant of these. However, if the Quay Quarter Tower model catches on and other flagship projects follow, there is no reasonable doubt that the decision to build sustainably will no longer have to be an end in itself, but can be based on sound economic considerations. Against this backdrop, national lawmakers will likely have little choice but to establish binding requirements for greater sustainability in construction in the future. It is to be hoped that this will be done with the necessary sense of proportion, so that the end result is a win-win situation for all stakeholders: building owners, the climate, the environment, and society as a whole.