Sustainable Building Features Foster Optimal Indoor Climate

A groundbreaking advancement in indoor humidity regulation has emerged from ETH Zurich, where a team of researchers has unveiled a novel material specifically designed to manage moisture in building environments. In settings ranging from busy office complexes to public libraries, excessive humidity can lead to discomfort and a rise in health-related issues. Traditional solutions often pivot around energy-intensive mechanical ventilation systems, which, despite their efficacy, contribute significant emissions and operate at considerable financial cost. Recognizing these challenges, the researchers embarked on a quest to explore passive solutions that align with sustainability goals.

The innovative approach taken by the researchers involves the use of a hygroscopic, or moisture-absorbing, material capable of effectively regulating indoor humidity. The essence of this technique lies in integrating specially developed components into walls and ceilings. These components capture excessive moisture during periods of high humidity and slowly release it back into the air when conditions allow for improved ventilation. Such passive methods promise enhanced environmental sustainability, reducing the carbon footprint associated with conventional mechanical dehumidification systems.

At the core of this research is the utilization of finely ground waste material from marble quarries, which adheres to the principles of a circular economy. By repurposing such waste, the project contributes to reducing resource extraction and landfill accumulation. However, to create robust construction materials from this powdered waste, a binder is necessary. Here, the researchers employed a geopolymer mixture that includes metakaolin, which has roots in porcelain production. Through a scientifically designed alkaline solution, the geopolymer compound facilitates the binding of marble powder into a solid construction material that performs exceptionally well as a humidity regulator.

The researchers succeeded in fabricating a prototype wall and ceiling component measuring 20 × 20 cm and 4 cm thick using cutting-edge 3D printing technologies. This method, known as binder jet printing, layers the marble powder, binding it solidly with the geopolymer compound. This process does not just allow for efficient manufacturing but also enables the creation of complex designs, making the application of such materials flexible and aesthetically pleasing.

The implications of this advancement extend into the realm of comfort within indoor environments. Building physicist Magda Posani led the study that corroborated the material’s hygroscopic properties. Analysis conducted during the research indicated that these innovative components could significantly mitigate discomfort stemming from high humidity levels in highly trafficked indoor spaces. Utilizing simulations, the research team observed that if a reading room designed for 15 individuals was outfitted with these hygroscopic components, the moisture-related discomfort index could potentially be reduced by 75% compared to a standard treated wall.

When considering alternative moisture-controlling materials, the study found that the newly developed components could outperform traditional clay plaster, a material known for its moisture resistance but with a limited water vapor storage capacity. Although the clay plaster was noted to be more climate-friendly, the innovative hygroscopic material demonstrated a greater capacity for absorbed moisture, establishing it as a superior solution for indoor humidity management.

Moreover, an important aspect of the research was the evaluation of the environmental impact over the lifecycle of these hygroscopic materials. The production and implementation of these new building components were assessed to result in significantly lower greenhouse gas emissions compared to traditional ventilation systems. This aspect is crucial, as more stringent climate targets necessitate innovative solutions that align with global sustainability goals.

Presently, the technology has entered the phase of further development and scaling for industrial production. This indicates the team’s intent to not only showcase a proof of concept but also to enhance and refine the production methods to meet market demand. Future research efforts in collaboration with other prominent institutions, such as Turin Polytechnic and Aalto University in Finland, aim to produce even more environmentally friendly wall and ceiling components, thereby contributing to a wider range of sustainable building practices.

The influence of these materials could extend well beyond mere building construction; they hold the promise of transforming how we engage with our built environments, enhancing comfort alongside making strides toward climate responsibility. The unique interplay of sustainability, cutting-edge material science, and advanced digital manufacturing methods is paving the way for a new era in architectural design and function.

In summary, ETH Zurich’s innovative research into moisture-regulating materials underscores the urgent need for passive solutions in modern building design. As cities become more densely populated and climate concerns rise, the integration of such technologies highlights a pragmatic method for enhancing indoor air quality while minimizing environmental footprints. The ingenious combination of marble waste, geopolymer binders, and advanced manufacturing techniques champions a new direction in sustainable construction that is poised to redefine comfort and functionality in architectural spaces.

Subject of Research: Moisture-regulating materials for indoor spaces
Article Title: Low-carbon indoor humidity regulation via 3D-printed superhygroscopic building components.
News Publication Date: 10-Jan-2025
Web References: http://dx.doi.org/10.1038/s41467-024-54944-1
References: Not available
Image Credits: Pietro Odaglia / Josef Kuster / ETH Zurich

Keywords

Hygroscopic materials, sustainable construction, humidity regulation, passive dehumidification, 3D printing, circular economy, climate impact, ETH Zurich.