Circular Design in Action: Upcycling Marble Waste into the SMARBLE Bathtub

The SMARBLE bathtub presents an innovative, value-adding solution to the waste generated from marble extraction. Whereas the reference product is made of solid blocks, the SMARBLE bathtub is made of small waste marble blocks collected from the heaps, which are assembled, glued and machined. The value proposition is therefore based on sustainability concerns, upcycling the marble extraction waste. Furthermore, the SMARBLE solution represents a significant reduction in CNC machining time leading to a reduction in energy and water consumption as well as in sludge generation. LNEG conducted studies with the company using its own methodologies with a view to create a more sustainable product.

Who did you help and what were their needs?

Formas de Pedra, a Portuguese company and client of the Enterprise Europe Network (EEN) Portugal since 2022, approached the network seeking support to develop new circular products from underutilized marble resources. The company operates in two main areas: marble extraction, supplying raw material to manufacturing companies, and design and innovation, focused on creating value from surplus material that cannot be transformed into commercial blocks.

Marble extraction typically generates a very low proportion of useful blocks. Only about 30% of the extracted materials can be commercialized as raw blocks, while the remaining 70% consists of smaller fragments that are usually accumulated in quarry heaps, with only a small share later used as gravel in construction.

To address this challenge, Formas de Pedra aimed to develop new products capable of valorizing these underexploited geological resources while integrating circular design strategies. The proposed solution is based on using marble components of different sizes, either in their natural form or assembled and bonded together, enabling the development of a range of new products from materials traditionally considered waste.

Beyond the technical and scientific challenges involved (such as identifying suitable binding materials), the company also needed to assess market acceptance for these innovative product solutions.

This initiative opens new opportunities to commercialize large quantities of currently underutilized secondary material by transforming them into high value products with timeless design, contributing to resource efficiency, sustainability and long-term value of real estate assets.

Services provided

Sustainability

What did you do to help them?

LNEG, through EEN Portugal, provided tailored sustainability advisory support to the company in the development of the SMARBLE Bathtub project, applying circular economy strategies under the “To Test Before Invest” framework.

The support process followed a structured methodology aimed at integrating sustainability and circularity principles into the design and development of a new product solution.

Characterization and analysis of the current business model, supported by the CE Designer tool. This step included the identification of company needs, key partners and cost and revenue models, as well as the definition of a prelimaniry value proposition for the new product.

Identification of opportunities to improving the business model from a sustainability and circular economy perspective, based on an categorization circularity strategies previously developed and applied by LNEG in several projects.

Analysis of the reference product from a design and circularity perspective, using the KATCH_e CE Designer tool. This phase aimed to assess the sustainability and circularity profile of the existing product (solid block bathtub), identify critical points with improvement potential, and determine relevant strategies and criteria for the development of a more circular solution, considering the entire product life cycle.

Co-creation and brainstorming sessions involving the design and development team of Formas de Pedra and the circular economy specialists from LNEG. These sessions supported the identification of improvement opportunities and potential technical solutions to be integrated into the new product concept.

Evaluation of the new product concept, developed by the company, through a second application of the CE Designer tool to validate its sustainability and circularity performance and to compare it with the initial reference product.

Support in defining an implementation plan and communication strategy for the improved product and the corresponding business model adjustments.

Preparation of the final technical report, summarizing the analysis, proposed improvements, and recommendations for implementing circular economy strategies.

The impact: What was the outcome of your help?

With the support of EEN Portugal, Formas de Pedra was able to assess the sustainability and circularity performance of its reference product and identify key areas for improvement. This process enables the company’s design and development team, working closely with LNEG, to create a new product with a significantly stronger circular and sustainability profile. The evaluation highlights notable improvements across several circular design strategies, as summarized below.

·Long Life Product Design - The evaluation of this strategy indicates a slight reduction in the new product due to the use of glue in the assembly process.

·Design for product life extension – Although this strategy was considered and integrated during product development, the evaluation result remains equivalent to that of the reference product.

·Design of product-oriented services - This strategy shows a significant improvement, increasing from 0% to 61%. In the initial model, the company did not provide services associated with the new bathtub. With the new bathtub, Formas de Pedra plans to introduce home-based repair and maintenance services, increasing user satisfaction and potential extending the product's lifespan.

·Design for recycling – Despite the relatively low evaluation, this strategy remains unchanged in the new product.

·Design for remanufacturing - The new solution presents slightly lower evaluation, reflecting the limited applicability of this strategy to this type of product.

·Design for material sustainability - This strategy shows a significant improvement using material that was previously rejected in the marble extraction process. By incorporating quarry waste into the product and improving communication about the product’s sustainability profile, the new solution strengthens the material sustainability profile.

·Design for energy sustainability - This strategy also shows a high improvement. The new production approach reduces energy consumption by shortening CNC machining and using materials with low embodied energy, as the marble components originate from recovered secondary materials from quarry heaps.

·Design of services oriented towards use or results - This strategy was considered not applicable to the product and project under development and therefore not included in the evaluation.

Overall, the support provided through EEN Portugal helped Formas de Pedra integrate circular design principles into product development, enabling the creation of a more sustainable and innovative solution based on underutilised marble resources.

This story is also featured in the catalog of women entrepreneurs, EEN TGWE – The New Edition of the 3-Minute Pitch e-Catalogue, highlighting innovative female-led initiatives and showcasing inspiring entrepreneurial journeys within the network.

Quotes from EEN partners and the company

I appreciate all EEN help in checking every detail, in developing the project, making it circular, and for all the clues you provided us, aiming its improvement. The company remains committed to continuing the concept in other pieces.

The new product - SMARBLE Bathtub

Production of the new product - SMARBLE Bathtub