OTTUMWA — The City Council appeared as nervous as cats on a hot tin roof.

They had good reason. The “roof” in question is actually a proposed steel roof system for the large hangar (also known as Building No. 23) at Ottumwa Airport. Replacing the hangar’s roof will cost about $457,047.

Why does it have to be replaced? The original roof built during World War II is still there and so are the repair efforts during the 1990s.

In asking for the council’s direction on how to proceed, Planning Director Dave Shafer offered the council a review of roofing systems and cost estimates prepared by Brown Engineering:

• The structural standing seam metal panel roof, also called the steel roof, would be installed on the existing slope of the roof with a 20-year warranty against leaks. Cost: $457,047.

• The screwed metal panel (exposed fasteners) roof would require an increase to the roof’s slope. Also, no warranty against leaks is available and the roof would require continued maintenance. Cost: $431,172.

• Roof membrane options include a single-ply rubber membrane with a 20-year warranty. The membrane has a 20-year warranty but won’t have the life of a steel roof. Cost: $439,770.

• MOD BIT, similar to the existing roof, will also have a 20-year warranty but won’t have the life of a steel roof. Cost: $462,306.

Councilman Gordon Aistrope said he was “extremely disappointed that the costs came in at double the amount he’d heard about.

“I’m tired of being between the rock and the hard place,” he said. “We need to do something ... If we don’t do this, then we’ll have [airplane owners] putting their planes elsewhere.”

The city’s insurance carrier has already handled claims concerning planes damaged by the leaking roof.

Councilman Tom Shepard said the steel roof is the obvious choice but he wondered if the city is basing the need for a new roof on the dream of a lot of large aircraft coming to the airport.

Shafer said a lot of corporate aircraft already comes and goes at the airport.

Tom Francis, airport manager, said Ottumwa Flying Service has planes there as does Indian Hills Community College and two other corporate entities. There are also several private plans there.

Aistrope said he doesn’t foresee Ottumwa adding a commercial air service but acknowledged there is a lot of corporate traffic.