Using resources more efficiently

Raw material consumption has increased significantly worldwide since 1970. The main reasons for this are a more resource-intensive lifestyle and the growth of the global population, which has doubled in the same period. Like many industrialized nations, Germany is facing the major challenge of significantly reducing its own resource consumption. Added to this is the volume of waste, as well as material shortages and challenges in the supply chains, which require a more resilient procurement strategy. A more efficient use of resources is therefore important in order to safeguard the quality of life of current and future generations.

BAU 2025, the world’s leading trade fair for architecture, materials and systems, will focus on resource-saving construction as a way to achieve sustainability in the construction industry. From using sustainable materials and the use of advanced technologies to conserve resources, to promoting the circular economy, BAU 2025 will showcase the latest technologies and strategies that are laying the foundations for the future of construction.

Focus on resource awareness

The sustainable use of available resources requires a rethink in all areas and between all those involved in construction. This includes, for example, the use of environmentally friendly materials and raw materials that are either recyclable, renewable or from sustainable production, and the reduction of the emissions and energy intensity of traditional building materials through new production processes.

© Messe München GmbH

The way buildings are used and operated also has an influence on the conservation of resources, for example through durable, sustainable structures, the efficient use of renewable energies, optimized building envelopes and intelligent building technology. However, no other topic engages the construction industry as much as circular construction. If we want to make it the standard across the board, we not only need recyclable building materials and components, but also a different kind of planning and single-origin construction.

From sufficiency to resilience

Sustainable development can be achieved through various strategies at different levels. The basic strategies of sustainability play a key role here: efficiency, sufficiency, and consistency. While the efficiency strategy aims to reduce input for the same output and the consistency strategy focuses on the development of durable and sustainable products, sufficiency strategies question usage-specific consumption patterns as regards what is “less” and “enough” in order to enable social justice within planetary limits. In the building sector, sufficiency addresses, among other things, the reduction of per capita space requirements, the prioritization of existing uses over new buildings, the adaptability and flexibility of rooms and buildings, as well as adapted usage behavior. A recent publication by the German Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) provides support for sufficiency approaches in the building sector. The low-tech approach can also be implemented at the design and building technology level through simple construction, lower fit-out standards, and energy-saving user behavior and thus reduced comfort requirements. The Einfach bauen (simply construct) research project deals with the issue of reducing the complexity of construction.

While sufficient approaches focus on reduction and efficiency, resilience ensures that buildings and infrastructures remain flexible and resistant to unforeseen events in the long run, such as short-term heavy rainfall or long-term changes due to climate change. Through robust construction and the integration of adaptation measures such as green roofs, water-permeable surfaces and the promotion of biodiversity, buildings and cities will become more resilient to environmental changes and at the same time contribute to improving the quality of life.

Is it all a question of material and construction?

The use of renewable, regional and local raw materials as well as old construction methods that are already known about plays a central role in promoting resource-efficient construction methods. In addition to wood, bamboo, hemp, flax, and straw, which already bind CO2 during their growth, other raw materials such as clay or lime also offer ecological and economic advantages, as they are available locally and also have an impact on supply chains and transportation routes. Whether straw can be spun into gold is still a question of time, but the variety of topics currently being addressed by the Ministry of Construction’s ZukunftBau research funding program by cooperating between university research and innovative companies points to the future.

In addition, the further development of building materials plays a major role in the future of the construction industry. Concrete and steel, which are responsible for a significant proportion of global CO2 emissions, are indispensable in the construction of buildings and infrastructure due to their material properties. Current developments show that substituting clinker with fly ash or granulated blast furnace slag, for example, can improve the CO2 balance. Research into carbon and gradient concrete also shows potential for the construction industry through material reduction and the targeted control of material properties, which not only enable new forms of architectural expression, but also help to reduce the life cycle costs of buildings and minimize their environmental impact. The format of the Bauhütte (side hut) or of a living world laboratory, based on the historical local associations of various trades, can also provide inspiration for further developments, such as the Bauhütte 4.0 of the TU Berlin in the Schumacher district in Berlin or the Marienpark Lab of the Bauhaus Erde initiative.

Hybrid construction methods, which utilize the positive effects of individual materials and elements in combination, are another way in which resources can be conserved. This results in connections with optimized properties such as higher strength and load-bearing capacity with lower weight, which enables the construction of larger and more complex buildings. Prefabrication, e.g. of timber hybrid elements, enables fast and precise assembly on the construction site, which shortens the construction time. A further advantage is the return to a material cycle through separability into the individual material components through single-variety planning and construction.

However, even with the best of intentions, conflicts of interest arise as a result of proposed legislation and regulation. Various stakeholders, including the Association of German Architects (BDA), have criticized the new model timber construction guideline, which thwarts the potential of timber construction methods, e.g. through encapsulation.

Circular construction: Resource efficiency and more

The use of recycled materials can also reduce the emissions associated with new production. In this context, the concept of the circular economy, often used synonymously with circular construction, stands for a paradigm shift in the construction industry: away from the traditional linear economy (make, take, waste) towards a sustainable circular approach (reduce, reuse, recycle). This not only saves resources, but also opens up new value chains and business models in the industry. This requires, among other things:

Design for dismantlability

Design for dismantlability, as explained by the Danish architecture firm Adept in its impulse on BAU Insights or by LXSY Architekten in the podcast of the Federal Chamber of Architects.

Closed material cycles

The Cradle to Cradle design principle and the use of durable materials contribute significantly to sustainability and efficiency.

Product-as-a-service / rental models

The manufacturers remain the owners of the materials, and are responsible for taking them back and reusing or recycling them at the end of their useful life, as the Lindner Group explains in the video article on BAU Insights.

Platforms for trading recycled materials

Platforms for trading recycled materials and/or reusable building elements, such as concular, Fibree or Block materials, working together in the “Closing the loop” pilot project as part of IBA’27, from inventory to platform creation.

The pilot project “Mining in the city: Heidelberg becomes Europe’s first recyclable municipality” shows that the economic cycle of materials not only works at the material level but also as an urban mine in the city. But even here, the potential has not yet been fully exploited.

Digital tools and resource management

An effective circular economy that moves towards a more sustainable and resource-efficient construction industry requires transparency about materials and resources, and a structure for tracking their use and optimally utilizing them over their entire life cycle.

A material register is a detailed list of all materials and products used in a building with information on quantity, location, condition, and environmental impact. Decisions on maintenance, refurbishment, dismantling, or recycling can only be made once the materials used have been precisely recorded.

The building resource passport goes one step further and provides comprehensive documentation of a building’s material and resource efficiency. It contains detailed information on the origin, composition, reusability, and recyclability of the building materials used, as well as on the energy efficiency of the building. In addition to the current call for tenders by the Ministry of Construction for the design of an overall approach to building information management, various players have already created facts.

Shaping the future: Resource efficiency as a guide

In view of global challenges such as climate change, scarcity of resources, and increasing environmental awareness in society, a rethink in the construction industry is essential. The future development of the construction industry therefore requires interdisciplinary cooperation and, above all, the courage to venture away from traditional paths.

BAU 2025 will not only offer an insight into current trends and innovations, but will also inspire and show ways in which each individual can contribute to a more sustainable construction industry. The future of construction is resource-efficient, and the time to actively shape this future is now.

Why build in a resource-saving way?

Resource-saving construction is important in order to protect the Earth’s natural resources and minimize the ecological footprint of construction projects. By using materials and energy sparingly, it helps to reduce CO2 emissions and waste.

What properties must an ecological construction material have?

An ecological construction material is sustainably extracted and produced, has a long service life, and is recyclable or biodegradable at the end of its useful life. It is harmless to health and has the lowest possible environmental impact throughout its entire life cycle, including transportation and processing.

When is a house sustainable?

A house is considered sustainable if it has as little impact as possible on the environment in terms of its use of resources and space, is energy-efficient and offers its residents healthy living conditions.