The cost of repairing a federal government office building in Gatineau, Que., that was badly damaged by fire two years ago has already exceeded the amount tax records indicate the building is worth.

Work to decontaminate the Louis-Saint-Laurent building on boulevard de la Carriè​re in Gatineau, Que., started Monday.

The top floor of the building caught fire in April 2016 while renovations were underway, doing considerable damage and forcing 1,800 employees with the Department of National Defence (DND) to move elsewhere.

Documents obtained by Radio-Canada show the government has so far spent $33 million on repairs, including $27 million for stabilization work that required 700 emergency steel posts to be installed. The government has also paid for assessments and a design for the repair project.

The $33 million doesn't include the decontamination work that started Monday, which is expected to cost an additional $5.8 million and wrap up by next summer.

In total, the bill adds up to approximately $38.8 million, with the potential for more expenses to come.

The city's latest property assessment valued the building's worth at $37.5 million.

Insurance costs still being determined

DND was the tenant of the building at the time of the fire, but even though its lease has expired since then, the government is required to make the repairs under the former lease's provisions.

The government had insurance, but the costs have not yet been resolved between the insurer, the government and the building's owner, according to Steve MacKinnon, the parliamentary secretary to the minister of Public Services and Procurement Canada.

He therefore can't yet reveal how much the government will be reimbursed.

"All of those things are being worked out," he said.

Steven MacKinnon, Parliamentary secretary to the minister of Public Services and Procurement, said the government is required to pay for the repairs. (Radio-Canada)

It's not yet known how much the government will pay overall, nor when or if workers will return.

"We are exploring all the options for the long term," MacKinnon said. "When we come up with a long-term plan we will be happy to communicate it."

The government and the building owner have also gone to court to settle some disputes, he added.

Conservative Quebec MP Alain Rayes said it appears the government isn't taking its financial obligations seriously, and is asking for more details about the repair project's financing.