Notre-Dame Basilica


Notre-Dame Basilica


Montreal, Quebec


Roof Restoration


Faucher Aubertin Brodeur Gauthier, Montreal, Quebec


Les Couvertures St-Léonard, Montreal, Quebec


Canadian Brass & Copper, Concord, Ontario


As any visitor to Montreal will attest, Notre-Dame Basilica in Old Montreal is one of that City's most notable landmarks, dominating the
Place d'Armes with its boxy façade and twin bell towers. The huge cathedral, seating up to 9,000 worshippers, was designed by American architect James O'Donnell who was based in New York. Construction began in 1824, and the towers were completed by John Ostell in 1841,
after O'Donnell's death.

The most recent restoration addressed some notable details, such as the flat seam cladding used for sides of the large dormers and the
detailed counter-flashings that were required between the stonework and the roof. Also unique to this project is the way that the roof steps
down into three segments, essentially three separate roofs. Another feature is the series of skylights that run along the 240-foot (73 m) ridge
of the Basilica. On the 80-foot (24 m) sloped sections, the batten-seam copper roof was installed using 8-foot (2.4 m) long pans, 18 inches
(450 mm) wide. It was installed over a fir plywood deck and a Roofshield™ membrane.

Approximately 65,000 pounds (29,500 kgs) of sheet copper was needed for the project. The roof pans are 16-oz. copper, while the
flashings are 20-oz. Also Architectural Bronze (Alloy C38500) extrusions were used to fabricate the snowguards.

™ Trademark

Adapted from Canadian Copper, No. 152.