The proposed University of Hawaii center that will house the late U.S. Sen. Daniel Inouye’s congressional papers is projected to come with a hefty price tag.

The estimated cost already has reached $25 million, up as much as 56 percent since June, according to UH documents.

And if the proposed Daniel K. Inouye Center is built for anywhere close to the preliminary estimate, it could become the priciest new building — on a per-square-footage basis — that UH has pursued in years.

The project’s anticipated construction cost on a square-foot basis would significantly exceed the tab of three of four mainland facilities the university cites as similar projects and potentially even the fourth, a complex honoring the late Sen. Edward Kennedy under construction in Boston.

Not even UH’s new $104 million cancer center — a biomedical facility with high-tech lab space, advanced ventilation systems and other specialized features — approaches the per-square-foot price being projected for the Inouye building.

The 150,000-square-foot cancer research complex in Kakaako, which opened earlier this year, was built for roughly $687 per square foot, according to an analysis of UH figures.

If the proposed 15,000- to 20,000-square-foot Inouye center hits UH’s estimated construction price of $25 million, the square-foot tab would total $1,250 to $1,667.

The $25 million estimate, disclosed in a July 24 UH document discussed at a Board of Regents meeting Thursday, was 25 percent to 56 percent higher than the $16 million to $20 million range the university identified in a June 3 solicitation letter to design firms.

UH officials did not respond to a Star-Advertiser request late Friday afternoon seeking comment on why the estimate increased dramatically from June 3 to July 24.

The newspaper emailed the request to four UH representatives at about 5 p.m., 20 minutes after the school provided the Star-Advertiser with the document disclosing the higher $25 million estimate.

Minnesota-based expert Bob Herskovitz, co-author of "Building Museums: A Handbook for Small and Midsize Organizations," agreed that the UH estimate was pricey.

"Although not unheard of, $1,250 to $1,667 per square foot seems pretty high," Herskovitz said in an email to the Star-Advertiser.

The building UH described in the June solicitation letter is similar to facilities built by small historical societies, and those structures typically have a library, archival section and museum, according to Herskovitz, an outreach conservator for the Minnesota Historical Society.

Museum magazine, a national trade publication, listed 11 new projects from 2003 to 2010 that were between 15,000 and 25,000 square feet, and the average price (excluding the most and least costly one) totaled $534 per square foot, Herskovitz said. The most expensive of the 11 topped $2,000 per square foot, but most were in the $300 to $700 range, he added.

INOUYE, 88, who served in the Senate for five decades, died Dec. 17.

By early June, the university already had issued letters seeking qualification information from consulting firms interested in planning and designing the Manoa center. A few weeks later, a selection committee interviewed the responding firms.

Industry officials say that was an unusually quick turnaround time for a project of this magnitude and with such a high profile, given Inouye’s stature.

UH expects the design work to be covered through donations and by tapping a research training fund bankrolled predominantly with federal money.

But UH officials eventually anticipate going to the Legislature witha request for construction funding, making the anticipated building costs of particular importance to taxpayers.

In written responses to questions the Star-Advertiser posed Wednesday before learning of the $25 million estimate, a university executive said the preliminary pricing for the Inouye project was on the high end mainly for two reasons.

After an economic recession that depressed construction prices in Hawaii for the past four years, UH officials believe the industry "will be in full recovery within the next year, putting tremendous upward pressure on construction costs," Associate Vice Chancellor for Research Vassilis Syrmos said in his Friday responses.

The Inouye center also will have unique information technology capabilities comparable to the Library of Congress, and that is expected to further increase construction costs, Syrmos wrote.

He also noted that the cost per square foot for laboratory-intense buildings — such as the cancer center — was $700 two years ago, while the estimated price for the same building today would be $800.

Although the proposed Inouye center is not a laboratory building, Library of Congress representatives reminded UH that the facility should meet the congressional library’s temperature and humidity requirements on an around-the-clock basis, with a backup system in place in case of power loss, according to Syrmos.

UH is joining with the Library of Congress to create a digital system for exchanging information from Inouye’s congressional papers.

Because of the Library of Congress standards, the mechanical and electrical systems of the Inouye center need to be at the same level as a laboratory-intense building, and the baseline cost estimates were premised on that factor, Syrmos said.

Even though several Star-Advertiser questions focused on why UH’s original estimate was so high, Syrmos did not mention anything in his written responses about the substantially higher estimate in the July document.

The newspaper on Wednesday also asked when the public would have the first opportunity to hear the regents vet this project.

Though UH officials were aware the proposed center was to be discussed publicly at the regents meeting the following day, they did not inform the Star-Advertiser. The public agenda made no mention of the project, which was discussed during the period devoted to capital improvement programs.

For an institution that has vowed to boost transparency and accountability in the wake of last year’s so-called Wonder Blunder, its handling of the Inouye project continues to generate criticism.

"From a taxpayer’s standpoint and from an alumnus of the University of Hawaii, we should be embarrassed by this lack of transparency and the runaway spending that continues," said state Sen. Sam Slom.

The university seems not to have changed its ways despite the Wonder Blunder and "continues to do business as usual," said Senate President Donna Mercado Kim.

Slom said he was particularly astonished that the construction estimate increased dramatically from June to July even though the regents had yet to publicly discuss the project and despite the tough budgetary climate.

"Sen. Inouye would be embarrassed by this," Slom said.

The university’s rush to pursue the project also has raised questions, which was the focus of a previous Star-Advertiser story.

In a rebuttal to that story posted on its website, UH emphasized that swift action was necessary because the U.S. Senate would store Inouye’s papers for no more than six months from the mid-February closing of his office, according to UH. That six-month period ended this month.

Asked why that factor would have any bearing on expediting a project not likely to be completed until 2015 or 2016 at the earliest, Syrmos replied that "while 2015 or 2016 may seem like dates well into the future, there is a requirement that stems from the archiving process."

Archiving Inouye’s papers is expected to take two to three years, and at the end of that period, the materials will need to be permanently housed and exhibited in a new home, Syrmos said.

"Therefore, the archiving process drives construction of the building," he added.

UH plans to construct the Inouye center on the site of Henke Hall, which is in dire need of repair, so this project will help address new-facility and deferred-mainte- nance issues on campus, according to Syrmos.

IN SENDING pitches for the planning and design phase of the project, UH referred to four mainland institutes — three completed, one under construction — as "similar in nature" and included information on each one.

Of the three already completed, none even reached $500 per square foot to build, according to a Star-Advertiser analysis, which converted all prices to 2013 values.

The only project that is comparable in price is the Edward M. Kennedy Institute in Boston. The construction tab for that 40,000-square-foot facility is roughly $1,350 per square foot, according to the newspaper’s analysis.

Syrmos said UH studied the Kennedy project and two of the others — the Howard H. Baker Jr. Center for Public Policy and Robert J. Dole Institute of Politics — to develop a size estimate for the Inouye building. The square footage total will be refined during the planning phase, he added.

Asked whether the Inouye center would be among UH’s most costly projects on a per-square-foot basis, Syrmos said it would be erroneous to compare this project to another building, partly because of the unique features planned for the Inouye facility.

The regents Thursday approved pursuing a consulting contract for the predesign phase of the project. The estimated cost of $500,000 will be covered by private funds, according to UH.

In the predesign phase, the university is expected to solicit public feedback as part of doing an environmental assessment.

State Rep. Isaac Choy, chairman of the House Higher Education Committee, noted that the planning is in the early stages and the projected numbers could change.

"It’s essential we get good value for the taxpayer dollars we spend," Choy said.