OTTAWA – Ottawa Fire Services (OFS) and the Office of the Fire Marshal have declared Friday’s (April 12) four-alarm fire in the Byward Market accidental.

Ottawa fire Chief Kim Ayotte called the fire “accidental and preventable,” in a news conference this afternoon at the scene of the blaze.

The commercial row building contains 12 units and four of those units sustained extensive fire and water damage.

“The Office of the Fire Marshal (OFM) and OFS has concluded its investigation of the fire that occurred at 35 William St. in the Byward Market on Friday,” OFS public information officer Danielle Cardinal released in a statement today.  The process involved a number of interviews and completing a thorough investigation of the fire ground. As per investigation protocol, the Office of the Fire Marshal was the lead organization managing the portfolio.”

Ayotte said the fire was caused by roofing activity that was being done on the building and the fire originate in the northeast corner of the complex.

While the location of the fire in the roof and cockloft burned through the building’s built-in fire separation measures, the chief said the “trenching strategy and aggressive extinguishing” prevented any further extensive damage to the other buildings in the row.

Ayotte could not divulge more details on the exact cause due to concerns of future potential litigation.

“The fire marshal and OFS investigators collaborated and together determined the cause was accidental,” Cardinal said. “The fire originated in the North-East corner of the roof of the building at 35 William Street where roofing work was underway. The commercial row building contained a dozen units, four of which sustained extensive fire damage.  The rapid-fire suppression activities and strategies employed by OFS are credited with saving the commercial complex. The location of the fire in the roof and cockloft surpassed the capacities of fire separation measures. The trenching strategy and aggressive extinguishing efforts ultimately prevented extensive damage in most businesses in that row. We want to thank those who provided witness statements and cooperated with investigators on scene.”