Students who apply for annex housing this year and are offered Harvard-owned apartments will not be allowed to change their minds and move back into their Houses, Housing Officer Lisa M. Colvin said yesterday.

Applications for the apartments at Peabody Terrace, the Botanic Gardens and 18 Banks St. are due today and Colvin said the office has already received a significant number of applications. The office will not have a final figure until tomorrow, she said.

Students who applied for annex housing last year did not have to sign a room contract when they applied. For the upcoming school year, students must commit themselves to living in annex housing when they turn in their applications.

The Housing Office will automatically cancel the House room contracts of the 98 students assigned to available spaces in off-campus housing, Colvin said.

Last year, which was the program's first, only 15 students from the residential houses moved into annex housing but 13 other people were offered apartments and failed to sign a contract. "A lot of people signed up and just decided not to do it," Colvin said. "We may have turned down some people who would have lived [in annex housing], and we couldn't get back to them."

With the exception of a few apartments in Peabody Terrace, the rent for annex housing has gone up in all threebuildings and will now range from $2400 to $4300for a nine-month lease, Colvin said. A house roomcontract costs $2400.

Most of the rents will increase by only $100 or$200 but unexpectedly high heat and electricitybills at 18 Banks St. have prompted the College toincrease the rent for those apartments by up to$1000 for the nine-month period, Colvin said.

The College rents all annex housing apartmentsfrom Harvard Real Estate (HRE), Harvard's propertymanagement arm, but the HRE bill to the Collegefor apartments at 18 Bank St.--unlike the chargesfor those in Peabody Terrace and the BotanicGardens--does not include heat and electricity.

As a result, housing office official estimatedthe probable cost of heat and electricity, andtheir guesses proved to be too small, Colvin said."It turned out to cost $300 per student for theyear," she said. "It was a lot more expensive torun [annex housing] there,"

College officials are looking into expandingthe program to other HRE buildings, but they havemade no plans for the immediate future, Colvinsaid