Amid growing controversy surrounding the decision to place brass bars in front of the books in the Dunster House library, House Masters Roger and Ann Porter have taken steps to defend their decision, citing security concerns and new information about the collection’s value.

When the Dunster House library opened Sunday for the first time this school year, residents discovered that their library’s collection had been rendered inaccessible, sparking a minor uproar on their House e-mail list, known as “Moose-droppings,” on Sunday and Monday.

Several students complained that bars would set an unacademic tone for the space, while others said that students should have been consulted in the decision. But the main worry appeared to be that students would no longer be able to access the books in the collection.

In an interview yesterday in the library, Ann Porter defended the decision and down-played the student reaction to the new security measure, striking the same chords she and co-Master Roger B. Porter had emphasized in a Wednesday e-mail to the House community. She added in the interview that students could still request books from the library and will now be able to access them 24 hours following a request, after library personnel have unscrewed the bars to remove the requested books.

The House moved to determine a way to protect the books after a visiting alum informed the House Masters this summer that there were some books in the collection that would be of some value, Porter said. She said she was unwilling to identify the alum out of concern for his or her privacy.

Some books have gone missing from the library over the years, Porter said.

“We noticed, occasionally, what looked like a gap in the books,” she said.

After consulting with officials in the University library system, several options were considered, including placing lockable sliding glass cases over the books, Porter said.

Students were not consulted in the process because it was made over the summer, she said.

Ultimately the Porters decided to go with the least expensive option, commissioning the placement of two rows of brass bars in front of each shelf of books, using already existing holes in the bookcase, she said.

Houses have had to trim costs after the Faculty of Arts and Sciences mandated a 25-percent cut in House budgets, which may have limited the House’s options when deciding how to safeguard the potentially valuable collection.

“It wasn’t our first choice,” Porter said.

She also said she wanted to find a way to maintain the library’s august character when selecting a means to ward off would-be thieves.

While Porter said she did not think many students regularly used the books, Sarah J. Johnson ’11, who sent an e-mail about the move over the House list, said she used the books regularly—particularly the reference books—instead of purchasing books for class.

She said the move goes against the nature of the University.

“My stance is the bars should come off,” she said.

Lorenzo Bartolucci ’11 called it a “sad day” when Dunster did not have enough money “to set up a proper library system.”

Former Dunster Undergraduate Council representative Matthew S. Garcia ’10 said he thinks the Porters’ recent e-mail to the house resolved the controversy.

“Most of it has been cleared up by now,” he said. “I don’t think people are really that upset about it.”

Both Dunster House Committee chairs declined to comment yesterday.

The Crimson broke the story of the new brass bars on its FlyBy Blog on Sunday.

—Staff writer Eric P. Newcomer can be reached at newcomer@fas.harvard.edu.