When Simon Mason first saw his future home in the Belgian hamlet of Elewijt, near Brussels, he thought all it needed were some modern electrical outlets, maybe a new kitchen and bathroom. But in truth, Villa Engels, designed in 1958 by the modern architect Lucien Engels, who lived there with his family for the next half century before moving into assisted living, was far from ready to accommodate Simon, his wife, and their two young kids.

Featuring an elongated glass volume supported by pilotis above a reflecting pool, the two-story house turned out to be in a sorry state when Simon, the head of a local chemical distribution company, bought it from Engels’s family in 2013. Major issues had been papered over for years.

Case in point: During the 1970s oil crisis, its vast floor-to-ceiling windows, which by then were hemorrhaging heat, made the house too expensive to keep warm, so the architect had resorted to boarding some of them up, and they had remained that way. But to fix it up, Simon would have to tread lightly around its creator’s vision—in 1992, while Engels still resided there, the house was landmarked for historic preservation.

Engels, born nearby in 1928, began his career by building housing developments for local workers and went on to complete other socially informed projects, such as holiday homes for working-class families along the Belgian coast. He also designed many of the Belgian pavilions at the World’s Fairs. In 1956, Engels went to America to tour some of Mies van der Rohe’s houses and had the opportunity to meet the Bauhaus master himself.

By the time Simon took possession of the 3,200-square-foot house, many of its concrete slabs were cracking and needed to be upgraded and reinforced. To help him with that and the rest of the restoration, Simon turned to architect and midcentury specialist Lotte Van Hemelrijck and to Thomas van Looij, an architect at Studio 22 in Antwerp who had refurbished another Engels residence, the Lambiotte House in Waterloo.

“We wanted to keep the spirit of the house,” says van Looij. What that meant, according to Simon, was keeping a few elements particularly in mind: “the marble, the original staircase, and all of the Wenge wood, which was the ‘in wood’ at that time.”

But retaining such elements did not necessarily come easily. The Wenge panels that line the back wall of the upper story, for example, had been warped by sunlight coming through the south-facing windows, as well as pierced to hang pictures and put in outlets. Van Looij and his team numbered each slat and removed and restored them in order to return the wall to a pleasingly warm shade of brown. Some were too damaged and had to be replaced.

“Like many architects of that era, he designed everything himself, from the door handles to the tables and chairs.” Simon Mason, resident

Engels had used the same wood to build a snazzy cocktail bar and coffee table. “Like many architects of that era, he designed everything himself,” says Simon, “from the door handles to the tables and chairs.” That’s why the house is so proportional. Simon notes that the width of the bar is the same as that of the cantilevered staircase that greets visitors in the entryway.

The restoration, according to van Looij, was “a balance between working on the design and updating the home’s structural integrity.” And the process was a revelation for all involved. As peeling paint was stripped back, the builders came across a surprise layer of straw that Engels had used as insulation, as well as an abstract mural that he’d painted downstairs but then plastered over. (The mural was refurbished; the straw had to be tossed.)

When Simon and van Looij consulted the original plans and considered how best to bring the house up to date, they decided to give the ground floor over to the children, transforming what had been the architect’s painting studio and his wife’s sewing room into bedrooms, while the garage, too narrow for any modern car, was converted into storage. The open-plan second story, which has direct access to the garden via an elevated, multilevel terrace, is the domain of Simon and his wife, Els. The living room is peppered with midcentury classics, nearly all of which were purchased secondhand, and then reupholstered, to save money.

Simon concedes that there were stumbling blocks during the three-year restoration. The cost of updating the window frames on the southern facade was astronomical. What’s more, the strikingly angular fireplace on the upper level hadn’t worked since 1990. The villa’s historic listing meant Simon couldn’t fix it the underlying issues, so his only option was to retain the concrete shell of the fireplace and build in a discreet fuel burner.

Despite these frustrations, Simon is clearly proud to be the keeper of Engels’s legacy. “We dismantled the house one tile, one piece of wood, at a time, and then rebuilt it to its former glory,” he says. “What we’ve shown our neighbors and the wider world is what’s possible with a house of this kind.”

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