Bibliothèque L'Octogone: A LaSalle Community Hub Reborn
Jul 16
5 min read
In LaSalle, a Montréal borough known for its cultural diversity, a beloved 1984 library has been given a second life — its original octagon preserved, its reach transformed, and its role as a community anchor reimagined for a new generation.
For more than forty years, Bibliothèque L'Octogone has been the pulse of daily life in LaSalle. Since opening its doors in 1984, no other cultural institution in the borough has drawn more visitors. Yet the building's own architecture — inward-facing and largely sealed off from the park and streets around it — had quietly limited just how much of that community life it could hold.
That tension is exactly what a 2017 design competition set out to resolve. In keeping with Québec's longstanding practice of using architectural competitions to shape its most important public buildings, the brief asked for something far bigger than a simple expansion: a 21st-century cultural institution that was accessible, flexible, sustainable, and genuinely rooted in the people who use it every day. Anne Carrier Architectes, in consortium with Labonté Marcil architectes, won that competition, and after years of public consultation, their vision has finally come to life.
Rather than tearing down what LaSalle already loved, the architects built their entire concept around keeping it. The library's distinctive octagonal volume remains fully intact, revealed rather than hidden, and extended upward through the addition of a new floor. The result grows the library's footprint from 2,645 square metres to nearly 4,500 — a dramatic increase achieved without pushing outward into the shared park beyond its walls.
That single decision carries real environmental weight. By reusing the existing structure — including portions of the original concrete slab and structural frame — instead of replacing it, the project avoids up to 261,000 kilograms of CO₂ emissions. It keeps 870 cubic metres of construction waste out of landfill. A high-performance building envelope, passive design strategies, and energy recovery systems push those savings even further, cutting overall energy use by more than 30 percent. The library is now pursuing LEED Gold certification, turning what began as a renovation brief into a genuine model for sustainable civic architecture in the province.
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
The new architecture takes its cues from LaSalle's own history, from the Lachine Canal to the historic Fleming Windmill, translating that heritage into a building that rises and flows rather than sits still. Visitors arriving from Dollard Avenue step into a soaring central hall first, the building's true hinge point, where the energy of the city gives way to the calm of the park beyond. From there, circulation opens out toward reading rooms, workshop spaces, rooftop terraces, and gardens.
Three distinct volumes, which the architects call "lanterns," give that circulation its shape and its purpose. The Urban Lantern rises above the library's administrative core at the northeast corner of Dollard Avenue and Salley Street, its glass façade animated by workspaces framed inside window openings inspired by comic-strip panels. To the southwest, the Pastoral Lantern leans toward Félix-Leclerc Park and the Aqueduct Canal, wrapping sunlit reading rooms and a generous outdoor terrace around the geometry of the original octagon below.
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
The third, the Community Lantern, holds down the southeast corner with a café, a news lounge, and a Fab Lab that spill out onto adjoining terraces and into a newly redesigned urban park. It's here that the building's public life feels loudest and most informal, tuned to the rhythm of the changing seasons outside. Together, the three lanterns do more than organize the floor plan — they turn the library into a genuine threshold, a place where the city and the natural landscape meet on equal terms.
Long before the redesign, Bibliothèque L'Octogone was best known for its comic book collection, and that legacy now runs through the building itself. The geometry of the interior spaces, the custom furnishings, and the wayfinding signage all borrow from the visual rhythm of graphic storytelling. Even the sculptural staircase joins in, its form feeling less like structural necessity and more like a panel pulled straight from a comic's page — the result turns a routine visit into something closer to flipping through a graphic novel.
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Natural light does its own share of storytelling. Interior belvederes — elevated nooks that open onto sweeping views across the library and up toward the sky — keep the building in constant conversation with the seasons outside its walls. Art carries that narrative further still: a living wall inspired by Hokusai's The Great Wave off Kanagawa brings texture and motion to one corner of the building, while a helical staircase carries En circulation, a suspended sculpture by artist Karilee Fuglem, guiding visitors toward a hushed reading nook known as Dans ma bulle — literally, "in my bubble."
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone hasn't been given a facelift so much as a second life. By protecting the octagonal form the neighbourhood already loved and building thoughtfully around it, Anne Carrier Architectes and Labonté Marcil architectes have shown that a beloved civic building doesn't need to disappear to be reinvented — it simply needs room to grow into what its community actually needs. As LaSalle's most visited cultural institution reopens as a genuine crossroads of city and park, culture and daily life, it offers a quiet blueprint for what public architecture across Québec might look like next.
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone. Photography by Adrien Williams
Bibliothèque L'Octogone.
Awards and honors
2026 Winner, Ordre des architectes du Québec Excellence Awards, Public Choice Award
With over 30 years of practice, Anne Carrier Architectes (ACA) has established a reputation for architecture that bridges bold contemporary design and the enduring character of the Quebec landscape. Based in Lévis, the firm is defined by a commitment to architectural excellence, where refined aesthetics meet rigorous technical precision.
The ACA approach is rooted in a deep sensitivity to site and context. By prioritizing light, material integrity, and spatial harmony, the studio creates environments that are both functional and emotionally resonant. Whether navigating complex institutional mandates or intimate residential projects, their work consistently reflects a dedication to longevity and timelessness.
The firm’s portfolio—ranging from public landmarks like the Octogone Library to serene private residences—demonstrates a persistent curiosity and a leadership-driven process that values collaboration. Through a synthesis of creativity and environmental awareness, Anne Carrier Architectes continues to shape the built environment, producing projects designed to withstand the test of time while elevating the experience of those who inhabit them.
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