Like most people in Mexico City that afternoon, Fernando Mesta and José Rojas remember September 19, 2017, for what it was: the worst day they’d ever had.

Mesta was attending a business lunch across town from Gaga, the gallery that the two operate from their home in Condesa, a reascendant neighborhood settled in the 1920s by the sort of families pictured in the Oscar-winning film Roma. Rojas, a trained architect, was in the gallery, a 1,000-square-foot converted garage. Working with a five-person crew, he was installing Gaga’s season-opening show when the floor slid out from under them. Their knees buckling, they ran for the street, only to find the doorframe so twisted that they couldn’t get out.

“It was super, super scary,” Rojas recalls of the magnitude 7.1 earthquake that ultimately killed more than 200 people in the city and caused extensive property damage in Condesa. Escaping through a door to the living room, Rojas made it outside just as an apartment building three doors down was collapsing. Turning back to his handsome gray-blue two-story stucco house, he saw chandeliers swaying. He remembers thinking, Oh, my God—it’s going to come down any second!

In Fernando Mesta and José Rojas of Gaga gallery’s study, artworks by Peter Wächtler, Josef Strau, Heji Shin, Matthew Langan-Peck, Danny McDonald, Mathieu Malouf, Torbjørn Rødland, and Giangiacomo Rossetti.

Photograph by Stefan Ruiz.

But the five-bedroom Deco-era house did not collapse or even crack. Antique dinnerware and ceramics propped up on a dining room shelf didn’t budge a centimeter, and none of the artworks fell off the walls. Just as remarkably, the towering 70-year-old cedars that shade Gaga’s semiwild garden stood their ground. “We were lucky,” Mesta chimes in. To get home that day, he walked an hour, reaching Rojas just in time to make another run for it. Avenida Ámsterdam, their arborlike street—one of the most beautiful in all of Mexico City—had sprung a gas leak. In a moment of tragicomic relief, they spotted an American friend, the musician and artist Kim Gordon, lost in the crowd. “We’d been planning to meet up later,” Rojas says with a dry chuckle. They then joined their neighbors to look for survivors and dig out the dead—four on their block alone. “We had no water for two days, no power for six, no Internet for a month,” says Mesta, now sitting calmly besides Rojas at their dining table, the center of their domestic life. “The only thing you could do to feel better,” he reflects, “was to help.”

As a couple and individually, Mesta and Rojas have likewise benefited from a little help from friends and family since meeting 19 years ago at Universidad Iberoamericana, a Jesuit university in Mexico City, hometown to the lanky 41-year-old Rojas. He grew up the son of a politician who was in a position to commission artists for public projects, and who, at different times, also ran the state oil and electric companies and was a board member of the national philharmonic.

In the gallery space, two works from the Cosima von Bonin show earlier this year.

Photograph by Stefan Ruiz.

Another view of the Cosima von Bonin show.

Photograph by Stefan Ruiz.

“He’s a great father-in-law!” Mesta crows with a typically broad grin, brushing back the waves of his longish brown hair. Mesta, 38, hails from Chihuahua, a high desert in northern Mexico, where his grandfather was a cattle rancher and his father is a lawyer. His mother was originally from Guadalajara—long a seedbed for creative talents—and, concerned that Chihuahua’s relative isolation would limit her four children’s worldview, she encouraged each of them to take a gap year in Europe before starting college. Mesta chose Paris.

He studied part-time at Christie’s but learned his future trade mainly at Air de Paris, a gallery named for a work by Marcel Duchamp. In 2004, when Mesta earned his degree in media studies, his Parisian mentors recommended him to Mónica Manzutto and José Kuri, the couple who started Kurimanzutto, arguably the preeminent contemporary art gallery in Mexico today, with a blue-chip roster that includes Gabriel Orozco, Jimmie Durham, and Sarah Lucas. At the time, Rojas was interning at Casa Luis Barragán, the former home of the Pritzker Architecture Prize-winning modernist, before taking off for a year’s graduate studies at Design Academy Eindhoven, in the Netherlands.

The house, seen from the garden.

Photograph by Stefan Ruiz.

Gifts from art world friends in the gallery office.

Photograph by Stefan Ruiz.

A painting by Juan José Gurrola.

Photograph by Stefan Ruiz.

Rojas and Mesta returned from Europe to a city in transition. Galleries, both commercial and artist-run, were ­prospering, as the collecting activities of Eugenio López Alonso, the Jumex fruit-juice heir who would go on to found the Museo Jumex, energized a new class of art buyers. ­Gabriela Cámara, another Chihuahua transplant, was presiding over Contramar, a restaurant in Roma that quickly became a clubhouse for both the local art world and globe-trotters jetting in to check it out. And Guillermo Santamarina—a revered teacher, curator, and performance artist—staged events that Mesta says galvanized the whole community. (It was a show by Santamarina that Rojas was installing when the earthquake struck.)

By then, Rojas and Mesta were dating. In 2008, Mesta rented the storefront next door to Contramar and founded the first Gaga, named not for the pop star but for borrowed lines spoken in videos by artists he represents, the visual poet Karl Holmqvist and Bernadette Corporation, a fashion-minded New York collective. Rojas explains they also liked the fact that, in Spanish, as in English, gaga suggests a doddering old person. From the start, Mesta positioned Gaga as a showcase for artists from abroad, opening with Claire Fontaine, a French duo he had met through their friend and colleague Eva Svennung. In under two years, the gallery was doing so well that Rojas closed his architecture studio to join the business, designing exhibitions and facilitating the production of artworks. “We couldn’t afford hotels or shipping,” Mesta explains, “so the artists would come for a month or more to work and stay in our apartment.”

In the living room, Rojas and Mesta lounge under a clown painting by Dennis Balk—to the left is a photograph by Art Club 2000, and to the right an artwork by Antek Walczak.

Photograph by Stefan Ruiz.

They lived in posh Polanco until seven years ago, when they bought the house and garden on Ámsterdam from Rojas’s father’s godfather, who’d built it around 1934. He’d intended the adjacent equally sized property to be the site of a second house for his three unmarried sisters. “In the end,” Rojas says, “they all lived in this house for the rest of their lives and put a badminton court in the garden.” They also planted cedars, which now help set the mood for parties, performances, and dinners.

“I think all of us in the art world here appreciate the unique personality that Fernando and José have given their home and gallery,” Manzutto says. “It’s been a very educational experience to see all of their artists in the context of Mexico and wonderful to see them embrace the local culture.”

Visiting artists occupy the two guest bedrooms on the second story, where the tile floor of a bridgelike passage running between their rooms and the master suite is embedded with small glass bricks. More glass bricks dot the patio outside a glass wall. After dark, light streaming through them into the gallery below creates a “spacey” atmosphere, Mesta says. All of these features are original to the house, as are the staircase and polished wood banister, the kitchen tiles, and the marquetry in the dining room, where the windows are a delicate leaf-patterned stained glass. Aside from turning the garage and a former library into the gallery and offices, the only other change Rojas made was to replace the wood-fired boiler with a new one fueled by gas.

These days, little evidence of the earthquake is visible along Ámsterdam, originally the outer circle of a ­hippodrome for racing horses around the Parque México, a glorious 22-acre green where swans glide across a lake and people stroll along winding pathways punctuated on ­Sundays by live music and dancing. Humps in the chipped sidewalk in front of Gaga—caused not so much by earthquakes as by the roots of evergreens that line the avenue—add character to a house that Rojas describes as “sober.”

The bar area, with works by Bernadette Corporation, Julien Ceccaldi, and Paulina Olowska.

Photograph by Stefan Ruiz.

“It’s not fancy,” he admits, pointing out that the sole ornamental details on the facade are the small ceramic tiles above the windows. The one real luxury is the garden; the interior is definitely lived-in, owing to furnishings that are all, with the exception of a “very expensive” bed, hand-me-downs: an aunt’s dining table, a grandfather’s desk (now a coffee table), a friend’s sofa. These days the pieces in their collection are mostly gifts, from artists including Alex Hubbard, who made the painting in the living room of a parrot drinking a glass of scotch. A striking portrait of Rojas by Julien Ceccaldi was a birthday present from Mesta.

Working and living together can take a toll on a relationship, but not theirs, Rojas says. “I think we have a very clear understanding of what we want and what artists we want to support.” Three years ago, their friendship with the New York artist-dealers Emily Sundblad and John Kelsey, of Reena Spaulings, resulted in a shared space, Gaga & Reena Spaulings Fine Art, in Los Angeles, where the two galleries hold exhibitions on alternate months. “The art world can be kind of cruel,” Mesta says, turning serious, “with everybody at each other’s throats and competing for clients, but I think I’m still sane because José and I are doing this together. It’s nice to go to an art fair in Miami or Basel and then be able to stay home and cook pasta. You know?”