The new Don Mills Ravine Home serves as a “cottage in the city” for a couple that loves to host and entertain. The generous lot falls away to a forested ravine and the design takes full advantage of the private 5,000 square foot urban oasis. Public spaces make up the length of the rear side of the house with expansive views and access to the backyard, pool, and terraces.

Project Name: Don Mills Ravine Home
Studio Name: Altius Architecture
Toronto, Canada
Photography: Revelateur
Building levels: 3

Don Mills Ravine Home by Altius Architecture - Sheet1
Living Room ©Revelateur

Development of the program and layout was driven by the owners’ desire to host large events as well as smaller groups of guests, while still maintaining the intimacy of a single family home from day to day. Amenities include an outdoor bar served from the kitchen, a backyard pizza oven and barbecue area, a change-room and bathroom accessed via the lower level walk-out for pool users, a game room on the uppermost floor with a treetop view, a wing of guest rooms at the second level, and a roof deck with gas fireplace.

The primary spaces are generous, with program revolving around a two-storey living room volume with a double height fireplace and curtain wall that connects the core of the building to the lush backyard and pool stretching back toward the ravine. The open tread steel and wood staircase allows natural light to penetrate from third floor down into the basement level, and at the second floor forms part of a bridge that divides the master bedroom suite from the guest rooms. A seamless connection to the outdoors is provided on all floors, including the basement with stepped planter walout.

Large aluminum-clad Douglas Fir operable windows, timber curtain wall, and sliding doors with glass guards acting as Juliet balconies brings the outdoors in. The material palette was inspired by a rocky beach cottage, with soft greens, blues, and greys. Oak, walnut, fir, zinc, and stone compose the natural material finishes, and provide warmth and texture in contemporary spaces. Engineered wide plank white oak floors sit atop hydronic radiant flooring. Ledgerock veneer wraps the main floor volume and elevator core, and slides from indoors to outdoors as a feature wall in the dining room.

Don Mills Ravine Home by Altius Architecture - Sheet2
Kitchen ©Revelateur

Flat lock and standing seam zinc panels clad the upper volumes and cover integrated rain water leaders. On the exterior, fir wood elements serve as shades and privacy screens to protect banks of windows from the sun and shelter outdoor spaces; while significant overhangs with fir soffits mitigate solar heat gain on the large expanses of glass. Natural light is abundant due to large windows, shallow building volumes, and generous building setbacks, and minimal artificial light is required during the day in the main spaces. The completed home is a warm and inviting space that connects its users to a lush urban oasis, and provides respite from the stress of city life.

Integration with the ‘Natural Assets’ of Site and Terrain
Site Specific View and Vista Optimization
Natural Daylighting
High Performance Envelope Design
Radiant Heating
Heat Recovery Ventilation
Solar Electric (photovoltaic or PV systems)
Low Energy Lighting & Appliances (LED, CFL lighting and Energy Star appliances)


With significant cantilevers, large fenestrations and deep shading overhangs, the Don Mills Ravine House structure is comprised of a significant steel frame, with moment connections and bracing, infilled with TJI floor and roof joists and wood frame walls.

Don Mills Ravine Home by Altius Architecture - Sheet3
Dining Space ©Revelateur

Curtain walls with glulam and solid fir as supporting structural members are the common language of the living spaces, with the most significant members on North and South sides of the two storey living room, and leading up to the third floor game room. Timber curtain walls with aluminum caps serve as supports for banks of glazing in smaller spaces such as the gym, sitting room, and game room. Operable douglas fir aluminum clad windows are used throughout provide for cross ventilation and passive cooling. The wood finish is left exposed on the interior for aesthetics, and the design takes advantage of the thermal properties of wood for a more insulated frame.

Heating is provided by hydronic tubes buried in a gypcrete overpour on top of the plywood subfloor. Ductwork provides for air conditioning and cooling, and acts as supplemental heating when required. Electric heatstrips buried in the wood soffits extend the useful life of outdoor spaces well into the shoulder seasons.

The owners, interested in sustainability, opted to install photovoltaic panels on less visible sections of the flat roofs. The discrete array generates an average 24kW of electrical per day, and as much as 60kW during peak solar days. The home therefore runs most of the time without pulling from the electrical grid, and has backup power in the event of outages in lithium battery storage. LED light fixtures were used exclusively in the home to reduce electrical consumption. In the front yard a subterranean cistern holds rainwater collected from the flat roof for irrigation of the significant landscaped space.


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