The Metrodome is getting a new $18.3 million roof for the Minnesota Vikings' last season there, even though it's not entirely certain it can be ready in time for the team's August preseason schedule.

And while the Vikings said Thursday that they supported the Metropolitan Sports Facilities Commission's plan to replace the stadium's 30-year-old storm-tossed roof, they reiterated that they don't see it as a long-term stadium solution and welcomed Ramsey County's plans to talk more with them about a possible stadium site in Arden Hills.

"Nothing's changed in terms of the challenges of [the Dome] in terms of fan amenities and revenues for the team," said Vikings vice president Lester Bagley. "We need to have a site and a local partner, and Ramsey County has stepped up. They have a viable piece of property, and we like it a lot."

Bagley spoke shortly after the stadium commission voted unanimously Thursday to install a new 10-acre cover of Teflon-coated fiberglass at the Dome.

Commission officials estimated that the total price tag for the project probably will be $19 million, including associated costs and fees. But they expressed confidence that the entire sum, save for a $25,000 deductible, will be handled by insurance.

The goal: Completion of the new roof by Aug. 1, only two weeks before the NFL begins its preseason schedule. Toward that end, the commission will pick a contractor based as much on ability to finish the job on time as on price.

It may wind up being the fastest public construction job since the rebuilding of the Interstate 35W bridge.

Ads for contractors to tear out the old roof and install a new one will appear in Friday's newspapers, with bid proposals due by Feb. 23, interviews on Feb. 24 and a contractor selected by Feb. 25.

"It's an aggressive timeline, but we need to take aggressive steps," said Steve Maki, the Dome's facilities and engineering director.

Maki said they know of only three contractors who can do the job, including Birdair Inc., which made and installed the old roof and inspected it as recently as last summer.

That inspection concluded that the roof was in need of some minor repairs but was essentially in good condition.

All of that changed with the Dec. 11-12 blizzard and subsequent periods of severe winter weather, Mark Waggoner, a structural engineer with the Texas firm Walter P. Moore, told the board at its special meeting Thursday.

Five of the roof's 106 panels were ripped open, four of them by weather and a fifth by a shotgun slug aimed at relieving pressure from snow and ice. But ongoing heavy doses of snow and ice, mixed with strong winds and low temperatures, were found to have torn, scratched, creased and dimpled the roof's Teflon coating in thousands of places, Waggoner said.

Engineers based their conclusions on more than a dozen samples cut out of the roof and tested for strength.

The damage left the roof's fiberglass yarns exposed to water, jeopardizing the fabric's ability to handle snow.

"While a number of them could be repaired through patching means and other repair techniques," Waggoner said, "their occurrence is so widespread that we don't know if it's feasible to reasonably, in the period of time that this building [needs to be] serviceable, commence upon a spot-based repair procedure."

Replacing panels was the solution used in the past to repair the Dome's roof, which deflated three times in the early 1980s owing to heavy snowfall. But in each of those cases, only one panel needed to be replaced.

This time, visual inspection alone found that nearly 60 percent of the roof's panels should be replaced, Waggoner said.

"But we do not recommend partial replacement," he said.

The board voted to certify the roof loss to its insurance carrier, FM Global. Officials said they expected FM to cover not just the roof but revenue lost for the period that the Dome has been unusable, under a separate policy for interrupted events. The commission paid an annual premium of nearly $260,000 for property insurance to FM last year.

Ramsey moves ahead

In Ramsey County on Thursday, Commissioners Tony Bennett and Rafael Ortega placed a resolution on next week's meeting agenda that authorizes the county manager to negotiate with the Vikings and develop a budget to analyze the former Twin City Army Ammunitions Plant in Arden Hills.

Bennett and Ortega said they have the votes to pass the resolution. "If you're not at the table, you don't get a chance to eat," Bennett said.

Staff writer Rochelle Olson contributed to this story.

Kevin Duchschere • 612-673-4455