A group representing 100 fraternities and sororities is lobbying Congress this week to urge legislators to pass a bill that would allow charitable donations to fund up to $1 billion in housing construction for Greek-letter houses across the country.

Fraternity and sorority leaders are seeking the passage of the Collegiate Housing and Infrastructure Act, which would amend the tax code to allow donations to Greek groups for student housing to be fully tax deductible.

The Fraternal Government Relations Coalition represents 725,000 undergraduates at 800 schools and collectively owns $3.2 billion in real estate. The new bill would spark countless renovations to outdated houses, said Jean Mrasek, chairman of the National Panhellenic Conference, which represents 26 sororities.

“We’re the largest landlords on college campuses coast to coast,” Mrasek said. “Our facilities are aging and they want to maintain their safety.”

More than 250,000 undergraduates live in fraternities and sororities, with some buildings dating to the 1930s. Some have seen few if any upgrades in the past several decades, said Wynn Smiley, chief executive of Alpha Tau Omega. Some facilities are in dire need of basic safety updates, such as fire suppression systems. Nationwide, just half of all fraternity and sorority houses have sprinklers, he said.

“If [the act] passed, they’d be renovated,” Smiley said. Mrasek added, “There’d be a construction boom.”

The Greek leaders say that with college debt growing, the bill could position fraternities and sororities to help students lower their college costs by offering cheaper alternatives to dorm housing. Room and board, Mrasek said, is higher than the tuition at some schools.

Under current tax rules, just 30 percent of a single donation to a Greek organization for housing is considered tax deductible. The bill would permit as much as 100 percent of the donation to be deductible, which already is allowed for donors who give directly to universities and colleges.

Supporters say the bill would grant tax parity between the colleges and the Greek houses that serve the same students.

“Universities already look to us to alleviate housing on campus,” said Tami Silverman, chief executive of Alpha Chi Omega. The bill would allow Greek groups to build “housing the students deserve,” she said.

The bill was first introduced in the House in 2003 by Rep. Paul Ryan (R-Wis.) and in the Senate by Sen. Pat Roberts (R-Kan.). The current bill, H.R. 1718, is sponsored by Rep. Pete Sessions (R-Tex.) and has 14 bipartisan sponsors. In March, the bill was referred to the House Ways and Means Committee.

More than 100 colleges and universities have offered support for the bill in recent years, according to the Fraternal Government Relations Coalition.

The group says that fraternities and sororities have identified $1 billion in construction and renovation projects that could begin if the bill passed.

“The Collegiate Housing and Infrastructure Act makes college more affordable for students, creates thousands of small business jobs nationwide, improves campus safety and reduces long-term student debt,” the group said in a statement. Passing the bill “would provide a meaningful long-term impact on small business job creation while improving the condition of nonprofit student housing for future generations of students.”