Slate is a metamorphic natural rock composed of clay minerals such as mica and chlorite, which give it a laminated texture and predominant shades of gray, black, and green. Widely used in the construction industry, it is known for its durability and distinct elegance, offering a timeless and sober finish for roofs and exterior walls. With its unique texture, it can transform the look of any structure using rectangular—or other shaped—pieces. Additionally, it is a highly resistant material to weather, fire, and environmental pollutants, ensuring long-term performance with minimal maintenance. Its eco-friendly production process, involving only raw material extraction and minimal processing, reduces CO₂ emissions, making it an ideal choice for sustainable contemporary architecture.
Specializing in roofing and cladding solutions, Cupa Pizarras is a Spanish natural slate manufacturer that operates as a carbon-neutral company and employs environmentally friendly practices in all its production processes. Below, we delve into four of their rainscreen cladding systems and provide practical examples of their use:
Modernity and Visible Fixings: 201 VANGUARD
The CUPACLAD® 201 VANGUARD range includes systems with visible fixings: stainless steel clips, slightly visible at the bottom, which contrast with the natural slate. This gives the facade a modern touch and a dynamic, yet predictable, pattern.
In this residence in Dollis Hill, UK, designed as a city escape, slate took center stage, covering almost the entire facade. The chosen system blends with other materials and the project's surroundings, providing a high-quality exterior finish. According to Ronan Glynn, developer at Talina Builders, "Natural slate is a great cladding product. Not only is it easy to install, but, as it’s natural, you don’t have to handle cost sheets for working with a dangerous material." He also highlights its easy reuse and long lifespan.
The range was also chosen for a major renovation of the Hørgården Care Centre in Copenhagen, Denmark. This project, initiated in 2015 and completed in March 2019, aimed to modernize the 1974 building to meet modern care center standards. Led by JJW Arkitekter A/S, the project focused on energy efficiency, accessibility, and equality, aligning with contemporary energy standards. With the help of slate cladding, the renovation became a modern building, and was even nominated for the Procesprisen 2018 award, which recognizes innovative projects that demonstrate close cooperation and transparency in construction.
Horizontality and Invisible Fixings: 101 LOGIC
The CUPACLAD® 101 LOGIC is a rainscreen cladding system that highlights the natural texture and shine of slate, composed of systems with invisible fixings and using 40×20 cm pieces that are installed horizontally.
In this project, the rugged coast of England inspired the replacement of a bungalow with a modern house. "We wanted a house that used a variety of materials for a modern look, avoiding an ostentatious glass palace," said David, one of the owners. George + Tomos Architects led the project, considering local restrictions and coastal durability, ultimately choosing CUPACLAD products. The waterproof cladding system, with its invisible fixings, enhances the beauty and durability of the natural slate, maintaining its immaculate appearance. Crucially, the material had to be resilient against strong winds, allowing the new house to blend beautifully with the surrounding cliffs.
In Peckham, a modern neighborhood in South London undergoing transformation with contemporary housing projects, a notable renovation on Costa Street transformed a housing block into a landmark. The building features a lower half of traditional brick and an upper half of natural slate, designed as a contemporary mansard to create dynamism in the volume. The designers chose CUPACLAD 101 LOGIC for its technical suitability and elegant appearance. Slate weighs just under 40 kg per square meter, compared to 150 kg of brick, and allowed for the desired tilt effect envisioned by the architects. The efficiency of the ventilated facade and the metal support system, which hides services and connects contemporary and traditional elements, were crucial in the decision. The aluminum system increases durability, reducing installation time and maintenance needs.
Dynamism and Creativity: 101 RANDOM
The CUPACLAD® 101 RANDOM system is composed of slate pieces of different sizes (50×25, 50×20, and 50×15 cm) installed horizontally with hidden screws. It uses self-drilling stainless steel screws with large flat heads, specially selected by specialized engineers to ensure perfect fixing and reduce installation times.
At Southern New Hampshire University, USA, a new building for the College of Engineering, Technology, and Aeronautics (CETA) needed an innovative design to reflect a 21st-century institution. Wilson HGA was selected to oversee the project, which had a variety of requirements: new classrooms, offices, libraries, and optimizing natural light. They chose CUPACLAD 101 RANDOM for its suitability to New England’s climate. "The project is a tribute to New Hampshire architecture, inspired by old covered bridges," recalls Christianne Peschard. The various sizes of slate create dynamic visuals, complemented by floor-to-ceiling vertical windows with wooden frames. Peschard also highlights the integration of slate inside the building, enhancing visual appeal.
Another example comes from Paris, France. Designed by ECDM Architectes, the building is part of an urban renewal project initiated by the City Hall in 2011 to revitalize the Binet neighborhood, located in the heart of Paris's 18th district, near Porte de Montmartre, with a stunning view of the Sacré-Cœur. It houses a 4-star hotel, a restaurant, meeting rooms, office headquarters, and a rooftop bar, all clad in CUPACLAD® 101 RANDOM slate. It features over 30,000 pieces of natural slate, forming an elegant and dynamic facade that resembles a black arrow pointing to the sky. The project highlights the elegant and durable qualities of slate, making it perfect for contemporary architecture and showcasing Cupa Pizarras' expertise.
Order and Homogeneity: 101 PARALLEL
The CUPACLAD® 101 PARALLEL rainscreen cladding system is composed of 40×25 cm slates installed horizontally, vertically aligned, and with hidden screws. The system shares the same invisible fixings, and two self-drilling stainless steel screws with large flat heads ensure easy installation and a perfect final result.
The system was used in Humboldt Park, an up-and-coming neighborhood in Chicago, USA, housing a transformed building on Fairfield Avenue, now one of the trendiest spots in the area. Through adaptive reuse, the building, once a noisy biker bar, gained new life and purpose after years of abandonment. Amy Yurko, AIA, founder of BrainSpaces Inc., saw potential despite its dilapidated state, opting for an innovative look to integrate with the neighborhood. The waterproof natural slate cladding system was chosen for its innovative style and uniform texture, covering nearly a hundred square meters of the facade with 40×25 cm slate tiles. This combination of natural slate and waterproof cladding offers efficiency, durability, and modern aesthetics. According to Amy, "Its elegant and timeless slate material changes appearance with the weather—shining when wet and matte and buttery when dry."
Another example is the original Fairfield Library in Virginia, USA, founded in 1976, which needed an expansion to meet new community demands. Architects opted for a contemporary solution, cladding the building's envelope with a natural slate screen. They ordered 1,500 square meters of the CUPACLAD® 101 system for the external facade, carefully considering local requirements before planning the expansion. In Virginia's challenging climate conditions, the system was chosen for its performance and distinctive aesthetics. Once installed, slate requires no maintenance, enhancing its appeal as a durable and aesthetically pleasing solution.
For more projects clad in natural slate, visit the Cupa Pizarras' website.
