A sustainability-­focused Honolulu charter school was facing the bleak prospect of shutting down over the summer as school officials scrambled to find a new campus to accommodate its nearly 200 middle schoolers after its Kaimuki lease ended.

Instead, SEEQS — the School for Examining Essential Questions of Sustainability — will be sharing a campus with Kaimuki High School, 2 miles away. The arrangement allows the charter school to remain in the East Oahu neighborhood and will provide SEEQS with classroom and office space, dedicated restrooms and shared use of the cafeteria and other open spaces.

But the biggest perk, says SEEQS founder and School Leader Buffy Cushman-Patz, is that the school will save on rent.

Unlike traditional Department of Education schools, which have free use of campus facilities along with utilities and maintenance, Hawaii’s public charter schools are expected to budget their state-funded per-pupil money to cover facility expenses on top of core operating costs.

“As a charter school we have very limited funding — on the order of $7,000 per student — and with that we have to pay for our facilities and all of our curriculum and teachers and operational costs of running the school,” Cushman-Patz said in an interview.

SEEQS, which started in 2013, had been spending $150,000 annually on rent and utilities for its existing site — a building owned by the Salvation Army on 22nd Avenue in Kaimuki. The expense swallowed 15 to 20 percent of the school’s budget. To keep up with student demand, SEEQS erected large vinyl tents on the Salvation Army property for added classroom space for its sixth-, seventh- and eighth-graders.

“It was a perfect place for us to start and to grow, and it was a nice community … but it just wasn’t a place where we could continue to grow,” Cushman-Patz said. “We were chartered to be a sixth-through-12th-grade school. Ultimately the vision was that we wanted to be about 400 to 450 students at full size.”

An initial two-year lease at the spot was extended for two more years, and the school is now on a month-to-month lease as it prepares for the move.

“I spent the last year exploring all the possible options,” Cushman-Patz said, including revisiting 38 potential sites she looked at when first opening the school. She said Kaimuki High was on her radar because she taught part time at the campus 15 years ago. She approached the school but was initially turned down — twice.

Wade Araki, principal at Kaimuki High, said after learning that the school essentially had nowhere else to go, he agreed to accommodate its students and staff on his campus.

“It was pretty bleak for the kids at SEEQS. It was either they find a place or they close,” Araki said in an interview. “To me they’re public school kids. I couldn’t see 180 kids having no place to go next year and having to find a new school.”

Araki said although he’s had to reconfigure some classrooms, the campus has space to spare. The urban school was built to accommodate roughly 1,400 students, but enrollment has remained at 750 students in recent years due in part to the aging population in nearby neighborhoods.

Cushman-Patz and Araki said the schools have similar philosophies, including an emphasis on project-­based learning. Neither school leader foresees any problems having SEEQS’ younger students, who wear bright-green uniform T-shirts, on a high school campus.

“Our school is based on community. We want to eventually be a sixth-through-12th grade school anyway, so we’re always going to have multiage learning happening,” Cushman-Patz said. “We want our communities to be able to engage with each other when it makes sense to do so, but at the same time, the space that we’re getting is an underutilized part of campus where Kaimuki’s students aren’t going.”

Under terms of the agreement, SEEQS will not pay traditional rent. “I didn’t bring them here to be a landlord and charge rent,” Araki said.

Dann Carlson, DOE assistant superintendent for school facilities, said a so-called “use of facilities” fee will be established but said the charges would be nominal to help cover utilities and other costs.

“Anytime we have an opportunity to partner with a charter school, we’re more than willing and want to take advantage of that,” Carlson said.

In all, SEEQS will be getting six classroom spaces, including a portable that was once used as a special-education classroom, an old science laboratory classroom and a large section of the school’s cafeteria. SEEQS also will install its vinyl tents at Kaimuki High in an open lot that once housed a janitor’s cottage and was being used for overflow parking.

The move has been designed to minimize any disruption between the two schools. For example, SEEQS will use a different entrance and exit on the Diamond Head side of campus for drop-offs and pickups to avoid traffic congestion; school start times, end times and lunch schedules will be staggered.

Araki has turned over the agreed-upon spaces to SEEQS, which is now working through logistics with utilities and permitting to set up its tents. If all goes as planned, SEEQS anticipates opening the new school year Aug. 10 at Kaimuki High.

Sione Thompson, executive director of the state Public Charter School Commission, said he hopes the arrangement will lead to more collaborations.

“Operationally, it’s very difficult to harmoniously run multiple operations on one property, and if this can be a successful model, I think it can open up doors,” Thompson said. “Hopefully, this can set precedent for future opportunities for charters and public schools to partner.”

With a few exceptions, most of the state’s 34 charter schools lease space for their campuses. Charters spent more than $5.3 million last school year on lease rent, according to the commission, which authorizes and oversees charter schools.