WEST ALLIS, Wis. (CBS 58) — The City of West Allis says damage from last week's fire at its new municipal building project is significant but less extensive than officials initially feared.

Following inspections by city officials, engineers and contractors, the city said the fire damage was primarily contained to the roof area above the second-floor parking garage.

The roof's metal decking, numerous conduits, drainage pipes and several light fixtures were damaged in the fire, according to the city.

Water used to contain the fire drained into the first-floor parking garage, prompting officials to further evaluate the stone base beneath the future concrete slab.

Office areas on the second floor were affected by smoke and debris but did not sustain any observed water damage. The city said those areas will require extensive cleaning and could require additional work on mechanical, electrical, plumbing and finish systems.

A third-party structural engineering firm inspected the building's structural components Aug. 24. A formal report is expected early next week and will determine whether any structural repairs are necessary.

A restoration contractor has begun work in the areas most heavily affected by the fire, beginning with the second-floor offices.

The project's insurance team has also recommended testing for combustion byproducts to determine which materials will need to be cleaned or removed.

The city engineer said the condition of the project is more encouraging than it appeared immediately after the fire. While significant work remains, officials now believe the damage is manageable.

The city expects to have a clearer understanding of how the fire will affect the project's construction schedule once the remaining evaluations are completed.