Off Plaza Building by L. McComber – Redefining Mixed-Use Architecture in Montreal

The Off Plaza Building by L. McComber is a forward-thinking mixed-use development in the heart of Rosemont, Montreal, blending residential, commercial, and professional spaces into a single, vibrant architectural statement. Designed to address the challenges of rising rents, limited urban space, and the growing demand for family-friendly housing, the project offers a blueprint for sustainable and community-driven city living.

A Vision Rooted in Necessity and Opportunity

Since its foundation in 2005, L. McComber has sought a workspace that fosters creativity, collaboration, and long-term stability. The rising cost of downtown rentals, combined with a shortage of affordable housing, inspired the team to create a building that serves both their practice and the surrounding community.

The chosen site—a deteriorating commercial property once home to the Maison du Rotin—offered the perfect opportunity. Located just steps from Plaza Saint-Hubert, the lot measured a modest 15m x 26m, challenging the architects to maximize its potential.

Innovative Mixed-Use Design

The solution: a four-story, 1,100 m² condominium housing 8 residential units and 2 commercial spaces. This compact yet efficient program includes:

• 4 townhouses with two levels of living space
• 2 penthouses with rooftop terraces
• 2 studios with direct courtyard access
• 2 ground-floor retail units

The design is organized around a central courtyard, which enhances natural light, cross ventilation, and community interaction. Two exterior staircases connect the street and alley via carriage gates, encouraging active circulation and visual openness.

Residential Units Designed for Families

To meet the needs of urban families, the project incorporates spacious, functional layouts and private outdoor spaces. The townhouses feature three bedrooms on the upper floor, while the penthouses and studios offer versatile mezzanine levels that can serve as offices, boudoirs, or guest rooms.

Each mezzanine opens onto a private rooftop terrace with green roofs and planters, promoting privacy, cooling, and urban biodiversity. Large windows and double-height living spaces flood interiors with daylight, creating a sense of openness and comfort rarely found in dense urban settings.

Integrating Commercial Space Thoughtfully

City regulations required commercial activity on the ground floor, turning what could have been a constraint into an asset. The shops are placed slightly below sidewalk level to maintain height limits while allowing generous ceilings. A central exterior ramp ensures universal accessibility and doubles as a pedestrian link to the residences.

Sustainability and Active Mobility

The Off Plaza Building prioritizes sustainable urban living by encouraging walking, cycling, and public transportation. Its central location allows both residents and the architectural team to reduce reliance on cars, fostering a more eco-conscious lifestyle.

All the photographs are works of Raphaël Thibodeau