BERKELEY — Growing up as a young girl who loved building treehouses with her two sisters in the woods of Marin County, Emily Pilloton felt there was always safety in creating her own spaces. So it’s perhaps not surprising that she would pass along that knowledge by starting the Girls Garage, a girls-only workspace for those who love to build and design.

“Maybe it’s because I’m an architect,” she said. “But I think that having four walls within which you can make whatever you want, physically, is probably the most empowering thing for a human being to do.”

Girls Garage, a 3,600-square-foot, one-of-a-kind workshop in northwest Berkeley, offers girls ages 9 to 13 a proverbial “room of their own” to create their own living spaces. Complete with a wood shop, a metal shop, a digital fabrication studio and a collaborative classroom, the studio space offers after-school sessions in intricate metalworking, screen printing for T-shirts, posters and bags, as well as woodworking and carpentry.

It’s one of the few, if only, places in the Bay Area exclusive to girls who have dreams to be builders, engineers and designers.

During a Monday after-school class, two teams of girls were assigned to “divide to conquer” the building of an art-piece-style chair fashioned of plywood panels and stitched together with zip ties. The students got busy, operating circular saws, power drills, clamps and vises.

Micah Heller and Mia Beeman-Weber, both 13 and eighth-graders at Willard Middle School in Berkeley, said they decided to take the class together because they love building things. With the help of her mom who is a trained architect, Heller built a table in her loft-style bedroom, and Beeman-Weber, who wants to be a mechanical engineer someday, built a shed with her family.

“I was excited,” Heller said. “It seemed like a good after-school activity. In a lot of art classes, they’ll tell you to draw an elephant, and then you draw an elephant. It’s not, like, open-ended. And I like open-endedness.”

The studio, which relocated in the spring, started officially offering classes two weeks ago in a new space on 10th Street, doubling the size of its former home in a workshop-style classroom at Realm Charter School in Berkeley. Girls from Berkeley, Richmond, El Cerrito, Oakland and beyond have begun flocking to the space.

Instructors preach and teach young girls to “FEAR LESS. BUILD MORE” a motto stenciled in large letters on its walls, alongside a long strip of impeccably organized, brightly colored tools. The airy, sun-filled space is designed to fuel creativity and open-thinking.

“I thought it was important to say, this is our space and no one else’s,” Pilloton said.

Pilloton founded the nonprofit Project H Design eight years ago to unleash the talents and passions of local students in the design, engineering and architecture fields. The nonprofit has taught design to hundreds of students — boys and girls — in a Studio H class at Realm, helping them complete community design and architecture projects, like building two homes for the homeless, the school library and new classrooms. She started a separate after-school and weekend camp for girls only in 2013, that has done similar projects, such as constructing furniture for women’s shelters and little free libraries. The camp shared classroom space at Realm until the recent move.

Pilloton, 34, who now lives in Oakland, said that the idea for Girls Garage came out of five years of teaching coed classes and being unable to ignore the differences in how young male and female students learn.

“I would have female students who were in class, and if I would say, ‘who wants the run the chop saw?’ I would look at them and I knew they could do it, but they wouldn’t say they wanted to,” she recalled. “So there was just kind of self-censoring that didn’t seem to be happening when we were one-on-one or when we were in a small group of girls.

“Boys just, in general, tend to be like, ‘give me the machete and if a tree falls, I’ll fix it,’ ” she said. “And the girls are like, give me all 12 steps, so I know I’ll do it right. … In this type of work, it requires a patience and a care … and being willing to think about it before you do it.”

Alejandra Utrera, 26, who teaches in the Girls Garage and Project H’s coed classes at Realm Charter, said that she’s seen firsthand just how transformative the classes can be.

“I think it’s empowering because females aren’t always told they can do these things, so it’s giving them the tools to figure things out on their own,” she said.

The annual budget for Project H Design is $357,000, and funding comes in the form of grants, corporate sponsorships and individual donations. The Girls Garage program budget is just under $200,000. Workshop tuition is $325, but half of the girls are enrolled on full or partial scholarships and pay between $0 and $75, depending on their family’s ability to pay, Pilloton said.

Pilloton said she hopes the courses will give her students an added confidence, since many times “we catch them in that transition from elementary to middle school, which for a lot of reasons, academically and physiologically, can be terrifying.”

She said they don’t “sit around and talk about puberty,” but the girls gain a heightened awareness of their changing bodies and how powerful they are through the daily practice of working with often heavy and dangerous objects. By lifting 60 pound bags of concrete and running circular saws, they are learning to master their own worlds, she said.

“It’s not like I’m trying to cultivate some class of angry feminists, but I do think there is a fire I want them all to have,” she said. “There are intangible things that I hope they’ll gain from the experience, an ‘optimistic chip-on-their-shoulder’ I’ll call it, one that says ‘don’t mess with me, I’m going to go and do something awesome.’ ”

To learn more about Project H Design and the Girls Garage, visit www.projecthdesign.org.