Beneath the stone, the light

• Renovation of the basement of a private home in the village of Monistrol de Calders, near Barcelona.
• Architect: Victor Bouman, Bouman Arquitectura
• Builder: Vicenç Autonell
• Craftsman: David Alberjon, Delacrem Pintors
• Material used: MORTEX®, BEAL International

A mineral and luminous transformation beneath a historic house in Monistrol de Calders

Located in Catalonia, in the province of Barcelona, the historic house of Cal Serni sits at the heart of the village of Monistrol de Calders, a small hamlet with rugged landscapes, bridging nature and heritage. This characterful place recently underwent a subtle architectural reinterpretation, blending the memory of the place with a contemporary gesture.

The project, led by Bouman Arquitectura, originally aimed to transform the basement into a wine cellar and gathering space for family. But a broader issue soon emerged: reconnecting this isolated level to the rest of the house.

During a previous renovation, the original staircase had been removed, breaking the physical connection between floors. Reinstating it in the same location became impossible. The solution? A spiral staircase was built into the center of the ground-floor dining room, giving the basement a rightful place again in the home’s daily life.

Light as a transformative vector

To support the basement’s renewal, the team worked on the only existing facade, creating openings. This not only streamlined access to the new staircase, but also flooded the space with natural light. Light now reveals with poetry the vaults, arches and stone walls, bringing breath and rhythm to what was once a dark space.

A single material was chosen to unify the new construction elements: the mineral coating MORTEX®. Applied to surfaces, floors and the staircase, it creates a continuous, luminous surface that softens the space while highlighting the contrast with the old materials. Its light shade (BM24) helps spread light into every corner, enhancing the space’s serenity.

Integrated, multifunctional, intelligent furniture

A linear, built-in piece of furniture runs along the basement walls and transforms itself according to use: it serves as a bench, sofa, sink, countertop and wine cellar. This furnishing, both aesthetic and functional, also acts as a moisture barrier, ventilating the ground-contact walls through discrete openings—sometimes grooves, sometimes through the wine bottle holes.

One of the most original elements is a wall perforated with dozens of holes, designed to hold wine bottles one by one, embedded directly in the wall. This storage system—daring yet minimalist—turns the cellar into a true visual installation: the bottles seem to float in the wall, creating an intriguing and elegant graphic play, both practical and unexpected.

Behind this furniture hides an air renewal system, ensuring a healthy, fresh, dry environment. A discreet yet essential solution to guarantee comfort in this basement space.

A demanding project executed with MORTEX®

For David Alberjon, the applicator in charge of implementation, the work at Cal Serni posed a real technical challenge.“The space was a former cellar, particularly humid. The architect chose MORTEX® for its ability to withstand humidity while offering a high-quality aesthetic finish.”

The spiral staircase, the project’s centerpiece, was covered with a continuous layer of micro-mortar MORTEX®, achieving a look that is both raw and refined, perfectly in tune with the spirit of the place. David Alberjon uses the phrase “imperfectamente perfecto” to convey the material’s charm—a subtle irregularity, nuanced liveliness: honest and distinctive aesthetics.

To ensure breathability, the application followed a complete technical system, with REPELOIL protection specifically chosen for this underground context. MORTEX® truly proved its worth in the most humid areas: “We applied the MORTEX® system to a wall directly in contact with constantly seeping rock. We chose to apply no additional protection, to observe the material’s behavior. The result: water continues to seep from the rock, but the coating remains perfectly intact.”

Beyond its resistance, the applicator highlights the product’s composition—95% of natural origin—as a major advantage in projects where technology, durability and aesthetic sensitivity must coexist. “I wholeheartedly recommend using the mineral coating MORTEX® in this type of project. It meets technical requirements while adding true architectural value.”

This project is an inspiring demonstration of what the MORTEX® system can offer when placed at the service of a sensitive architecture that respects the character of a place.