Get ready to say goodbye to the Peace Tower's green roof
New brown copper could take decades to turn green again.
By Ben Andrews, Ottawa Citizen
Published Apr 16, 2026 | Last updated 4 hours ago
Behind a shroud of scaffolding, more than half of the copper on Parliament Hill’s Centre Block roof has now been removed as part of the ongoing multi-billion-dollar rehabilitation project that will soon leave the iconic Peace Tower topped with an unfamiliar colour for years to come.
Public Services and Procurement Canada (PSPC), the federal department overseeing the project, says construction work on the roof is well underway.
In an email, PSPC spokesperson Michèle Larose said the Centre Block rehabilitation project is “in process” of replacing the copper roof on Centre Block, including the central Peace Tower, though she did not say when work on the tower itself would begin.
“This new roof will take many years to oxidize and turn from brown to the green patina colour that is typically seen,” Larose said.
The rate at which copper develops its characteristic blue-green patina, a layer of corrosion due to oxidization, depends on local environmental conditions. It may take anywhere from five years to decades to form.
The government says the Centre Block rehabilitation is the “largest, most complex project to rehabilitate a heritage building ever in Canada.”
The work is being done to restore crumbling stonework, earthquake-proof the building, remove asbestos, replace outdated mechanical and electrical systems and build a new welcome centre.
Starting this summer, the Peace Tower will be covered in steel scaffolding and cloaked in a decorative wrap with images of the tower hidden underneath. The $4-million wrap is known as a trompe-l’œil, or trick of the eye, and is meant to mitigate negative effects on the local tourism industry.
As part of site preparation for the project, about 21,000 kilograms of copper will be removed so the roof can be rehabilitated and restored.
According to the government’s latest quarterly update, more than half of the total copper has already been removed and overall roof removal sits at about 30 per cent.
“That is equivalent to (16,021 kilograms) of copper available to be repurposed,” the update said.
Overall project cost and schedule are “progressing but experiencing challenges,” according to the update.
As of March 13, spending on the project had reached $1.66 billion out of a total estimated cost of $4.5 billion to $5 billion.
Replacement of the roof, including the Peace Tower roof, will continue “over the next few years,” LaRose said. Overall construction is expected to be completed between 2030 and 2031.
https://ottawacitizen.com/public-service/peace-tower-green-roof-parliament