Hangar One is about to shed its skin.

A contractor is set to start tearing the walls off the landmark Moffett Field structure next week, though it is not known on which day, Navy Base Closure Manager John Hill said Tuesday.

Hill said the Navy’s contractor, United Kingdom-based AMEC, will begin by removing panels on the southern side of the hangar and work northward. Work is expected to be finished at the end of this year or early next year.

Workers have spent the past several months dismantling the interior of the hangar, and removal of the walls will culminate a years-long fight by preservationists to save the structure.

The Navy, which operated Moffett Field until 1994, is responsible for cleaning up toxins on the Superfund site, including the PCB-laced panels of Hangar One.

Meanwhile, NASA’s plan to replace the hangar’s walls appears on track.

NASA Ames officials did not return requests for comment, but the agency issued a “request for information” Friday from contractors interested in restoring the structure.

“NASA’s intent is to rehabilitate the hangar with new metal siding, restore the historic windows, install a new roof on the upper crown of the hangar and return the hangar to a state of usefulness,” the request says.

The request for information document suggests the hangar’s historic corrugated windows may be saved, as hoped by many hangar advocates. The Navy said earlier this year that NASA Ames needs to put up as much as $1.2 million by mid-February to save the windows, and preservationists are scrambling to raise the money.

“Navy and NASA are in discussion on how best to address NASA’s interest in the corrugated windows of Hangar 1,” Hill wrote in an email Tuesday. “No decision has been reached, but we plan to conclude this matter before the end of the month.”

NASA issued a similar request for information in August, but officials reported they received only a few “partial responses,” which Director of Center Operations Deb Feng said was “a little disappointing.” It was not clear Wednesday how the new request differs from the one issued in August.

Responses to NASA’s request for information are due April 19. The document estimates the cost of restoring the structure at more than $25 million.

Finding the money to restore Hangar One had been the biggest obstacle to its preservation, but the proposed federal budget President Barack Obama released in February for next fiscal year allocates $32.8 million to NASA for the work. The request still must be approved by Congress, which today could vote on a 2011 budget deal and has not yet tackled next year’s budget.

Email Diana Samuels at dsamuels@dailynewsgroup.com.