P.E.I.'s Province House may need to be shut down for as long as three and a half years for repairs that could cost tens of millions of dollars.

The extent of water damage in the building is outlined in a 500-page report commissioned by Parks Canada from Toronto architects Taylor Hazell. The report was commissioned in September 2012, delivered in May 2013, and only released to the media following an Access to Information request.

Province House is currently closed for repairs to plaster that has been falling from the ceiling, as well as to gutters and downspouts. It will reopen for the spring session of the legislature, in about three weeks, but the current repairs are just the beginning of a project that the architects say will likely go on for years and require an extended closure.

News of the state of the building comes out in the year the province is celebrating the 150th anniversary of the Charlottetown Conference. That meeting, held in Province House in 1864, started the talks that led to Confederation.

Provincial Progressive Conservative Party Leader Steven Myers said it is important that the repairs be done.

"It is a great building and it's got lots of history," said Myers.

"I'd like to see the repairs done so that we could at least be able to hand this on to future generations."

Safety issues

Province House renovations

Province House has been closed for repairs since February, but will reopen for the spring session of the legislature. (CBC)

It did not take long for the architects to identify some big problems. Just over a week after they started their investigations, they issued a preliminary report with the following statement.

"The extent and nature of the deterioration appears to be significant enough that a sudden wall failure event could occur that could endanger health and safety of the public or building occupants."

The problem lies in the very nature of the way the walls are constructed. They are done in two layers, with an exterior wall of granite, and interior wall of Island stone. The two are held together by mortar and timbers. Those timbers are rotting, and the mortar is disintegrating.

The architects found water has flowing from the roof for years, in between the two layers of stone. They wrote of hearing "rushing water" between the walls.

The architects saw cracking of the mortar joints, bulging of some exterior walls, and long vertical cracks that they say indicates destabilization from the foundation upward. They write the stone has been saturated with water and has become "fractured, soft and deteriorated."

"This problem must not be taken lightly as any significant vibration source could trigger a collapse of an area … which would pose a public safety hazard," they warned.

Parks Canada declined to be interviewed on the issue, but in an emailed response wrote they believed proper precautions had been taken.

"The engineering firm clearly stated that the building is safe for its intended occupancy," wrote external relations manager Jennifer Stewart.

Trouble with the roof

The source of the problem appears to be the roof, which was retiled with slate in 1980, replacing asphalt shingles that had been there since 1935.

'Province House National Historic Site has benefitted from over $6.6 million in investments by Parks Canada since 1974.'- Jennifer Stewart, Parks Canada

"The replacement roof is not performing well: leakage is occurring at the eaves and valleys, and slates are cracking due to freeze-thaw issues," the architects write.

"Overall resistance to driving rain is poor."

The slates on the 1980 roof were laid with a 7.5 centimetre overlap, which the architects say is probably insufficient. The roof also lacks a ventilated space underneath to allow drying.

Repairs are needed through the whole building. The architects recommend doing the work from the inside out, which would require the removal of all the interior walls, plaster and wood trim. They say they don't know of any other way to do the repairs that will maintain the heritage character of the masonry.

They estimate the work will take three and a half years, and recommend the building be closed during that time.

The section of the report that estimates the cost has been blacked out in copies provided to the media, but federal and provincial officials say it could be between $30 million and $40 million.

In its email response, Parks Canada said commissioning the report is part of a process to ensure the survival of the building.

"[Ottawa] recognizes the significance of Province House which is intrinsically tied to the founding of Canada and is taking important steps to ensure the integrity of the building for all Canadians, for all time," wrote Stewart.

"Province House National Historic Site has benefitted from over $6.6 million in investments by Parks Canada since 1974, including more than $2.6 million in recent conservation work."

Provincial Infrastructure Renewal Minister Rob Vessey declined to be interviewed.