flexform groundpiece

6 Architectural Projects Featuring the Iconic Groundpiece Sofa

Here’s why architect Antonio Citterio’s influential sofa design is a global best-seller.

Architizer Editors Architizer Editors

Antonio Citterio was destined to design. Ingrained since birth in the Brianza design district of his native Meda, Italy, home to numerous multi-generational furniture makers, the culture of his upbringing encouraged a creative output that includes individual buildings, countless residential interiors and, perhaps inevitably, world-renowned furniture.

flexform groundpiece

Architect Antonio Citterio at his desk

Dabbling beyond the confines of a formal background in architecture, Antonio began collaborating with local furniture maker Flexform over 40 years ago, quickly becoming one of the firm’s go-to designers. This partnership, which has been so prolific that Flexform refers to him as a “deus ex machina,” led Antonio to design one of the most iconic creations of his career: Flexform’s Groundpiece sofa.

flexform groundpiece

The iconic Groundpiece sofa by Flexform

The best-selling Groundpiece, initially introduced in 2001, marks a notable departure from traditional sofa design. Deep and low, its proportions are tuned to a diverse range of contemporary activities, from watching to TV or accommodating overnight guests to a more recent proliferation of phone, tablet, and laptop use.

In line with its popularity, Citterio’s vision for the Groundpiece has been realized in projects around the world. Here’s a few of the best.

Miami Penthouse by Andrea Chicharo Arquitetura, Miami, FL, United States

Featuring deeply toned leather, the Groundpiece system used in this high-rise residence is especially notable for the family of furniture that surrounds it. A chaise lounge, a pair of settees and an additional sofa, all designed by Antonio Citterio, define multiple zones of activity in an otherwise open floor plan.

Citterio’s approach to furniture design, which considers collections and groupings instead of individual pieces, is a hallmark of his collaboration with Flexform. Drawing on his experience as an architect, the design of his furniture is always cast in terms of context, considering how it will fit a space that, in turn, fits the building around it.

Proa by Terraza Balear, San Agustin, Spain

This collection of Mediterranean retreats in Mallorca exemplifies one of the Groundpiece sofa’s signature design features: a limited, but very intentional, use of fabric colors. Inspired by Italian painter Giorgio Morandi, known for domestic still lives casting warm colors in cool light, the Groundpiece’s palette of comforting earth tones is both flexible and specific.

Composed of a range of light and dark browns, tans and ivories, this spectrum was picked to ensure the Groundpiece consistently imparts the same sensations as in the Proa project: allusions to sand and sun, and the undeniable feelings of peacefulness they’re associated with.

flexform piece

Loft On the Middle by DE & DE, Saint Petersburg, Russia

In designing the Groundpiece, Antonio Citterio said, “Each and every sofa sets the scene for a medley of different uses.” This is particularly true in the limited space of an urban apartment, such as “Loft On the Middle”. In a space like this, the sofa may be simultaneously used for activities as disparate as relaxation, work, or dining.

To respond to the ever-changing habits found in today’s domestic sphere, Citterio endowed the Groundpiece with a multi-functional armrest. Able to be padded in the same fabric as the sofa or replaced with an open, cowhide covered metal console, the Groundpiece modules in this home are configured flexibly enough to accommodate nearly any form of use.

flexform groundpiece

Object 329 by Meier Architekten Zurich, Switzerland

The unusual proportions of the Groundpiece sofa were a perfect fit for this hillside home in Switzerland. With an emphasis on long, horizontal lines, the dimensions of the Groundpiece mirror the dimensions of the house itself, making it a comfortable addition to an open plan living room. Placed alongside a dramatic picture window, the sofa frames a view of the surrounding countryside for those sitting on the couch without blocking it for anyone else in the room.

flexform groundpiece

South Yarra Project by Studio Lancini, Melbourne, Australia

The tonal range of the Groundpiece sofa found an appropriate application on the ground floor of this Melbourne home. Situated in a temperate climate, the living area’s primary wall can be opened completely to an adjacent garden, creating a large, indoor-outdoor room.

Finished in an ecru-colored fabric, the upholstery chosen for this Groundpiece assembly complements the floor’s tile, a large rug and much of the other furniture in the space, both inside and out, making it well suited to an open-air environment.

flexform groundpiece

BG Apartment by Francesc Rifé Studio, Seville, Spain

Multiple living areas are created with the application of this Groundpiece in a Seville apartment. Because the sofa can be configured in such a manner as to define multiple living areas, the designers of this space have employed it to demarcate separate zones for watching TV and gathering around a fireplace.

The Groundpiece’s versatility is further utilized with both the armrest and console options as end pieces, varying activity choices available in those areas. The thoroughness of Antonio Citterio’s vision in designing the Groundpiece is complemented on an adjacent wall, which features two chaise lounges also designed by Citterio.


Flexform’s Groundpiece sofa embodies everything that the manufacturer stands for — it is simple yet sophisticated, smart yet comfortable, modern yet timeless. As evidenced by these projects, the sofa’s design is a testament to Citterio’s understanding of the intimate connection between furniture and the architecture that surrounds it. It will be fascinating to see how this understanding manifests in Flexform’s future pieces.

To explore more product options from this groundbreaking company, check out Flexform’s website now.

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