Ventilation Building for CN Rail Thornton Tunnel

Hidden in plain sight, the Ventilation Building for CN Rail Thornton Tunnel has intrigued Burnaby residents for decades. This unassuming structure, masquerading as a typical house, stands on the corner of Frances Street and Ingleton Avenue. It’s a far cry from the usual industrial architecture associated with railway infrastructure. The Ventilation Building for CN Rail Thornton Tunnel isn’t a home, though. It’s a crucial component of the Thornton Tunnel, a 3.4-kilometer subterranean passage used by CN Rail. The tunnel, built in 1968, connects the Ironworkers Memorial Bridge to the CN main line near Lougheed Highway. It runs beneath Burnaby, carrying freight trains under our very feet. This “house” sits 45 meters above the tunnel’s midpoint. It houses powerful fans and ventilation systems. These systems are essential for clearing the tunnel of locomotive exhaust. This ensures safe oxygen levels for the crews of subsequent trains. The Ventilation Building for CN Rail Thornton Tunnel’s disguise is a deliberate choice. CN Rail opted for this unconventional design to avoid an “unsightly concrete box” in a residential neighborhood. So, they cleverly disguised the ventilation shaft as a house, complete with landscaping. Look closely, though, and you’ll notice the lack of windows, the metal “keep out” fence, and concrete barriers in place of a porch. These subtle clues reveal the building’s true purpose. Before an upgrade in 2022, clearing the tunnel took about 20 minutes, limiting its capacity to roughly two trains per hour. The upgrade cut the ventilation time in half, improving efficiency. This peculiar structure is a testament to ingenious engineering and a unique piece of Burnaby’s history. The Ventilation Building for CN Rail Thornton Tunnel stands as a quirky reminder of the hidden world beneath our feet.