How Mixing Materials Brings Luxury to Interior Design

MILAN HAS A GRITTY GLAMOUR that doesn’t endear itself to every visitor, but on my first visit I was surprised how much I liked it. From the imposing, imperial stone behemoth of Milano Centrale train station, I walked down the dusty, grand streets straight to the Villa Necchi Campiglio, a 1930s house and walled garden set like an emerald in the heart of Milan.

I’d wanted to go ever since I saw Luca Guadagnino’s 2009 film “I Am Love,” in which the house served as both the set and soul of the story, a restrained but sumptuous vision of Italian architecture. Designed by fashionable Milanese architect Piero Portaluppi and built between 1932 and 1935 for the wealthy industrialist Angelo Campiglio, his wife and her sibling (the Necchi sisters) the house affirms that the jewels of Milan are often found behind lock and key.

Thanks to heritage foundation FAI (Fondo Ambiente Italiano), the luxurious glass doors of the once-private residence now admit visitors. As I wound my way through its garden, golden light filtered through century-old plane trees, dappling Japanese anemones and ferns. Bands of marble, granite and ceppo stone wrap the facade of the home, its otherwise forebodingly glamorous entry softened by semicircular steps. I braced myself and entered.

Elegance is rarely more faultless than the home’s soaring ground floor, from its walnut and rosewood parquet to its briar-root panelled walls and broad staircase with Greek-key balustrade. Works by Morandi and Modigliani, found throughout, add another layer of refinement.

“The story of the house tells the story of Milan,” said Marco Fincato of the FAI. “It combines the power of industry, fashion and design.” Portaluppi’s gift was mixing luxurious materials and references, from the sensuality of Art Deco to the rigour of Italian Rationalist architecture. Rationalism was essentially a fascist movement, said Mr. Fincato, and while Mussolini’s regime proved ruinous for Italy, the resulting influx of money and power gave architects a brief chance to shine.

Shine, the Villa Necchi does. A wall of brass-trimmed, double-paned windows defines the sparkling glass veranda. As if in a greenhouse, plants grow in the 12 or so inches of space between the two panes. Uninterrupted views of the garden, jadeite s-curved upholstery and the geometric check of the green marble floors boost the sense of verdure. A lapis lazuli side table faces an 18th-century Japanese lacquer cabinet, exemplifying the way the Villa’s materials complement, and contrast with, each other.

It feels as though Portaluppi has dressed the house with different finishes to send her off for a glittering night of opera at La Scala. Each room features sliding doors inset with mercury mirror or interlocking bricks of silver alloy. They open with a whisper and lock down like a fortress. Goatskin-parchment paneling swaths the dining room, whose plaster ceiling is spangled with constellations. Even the radiators sport bespoke brass chain-mail covers that swish like earrings.

As Marianna Kennedy, a designer whose eponymous atelier in London is renowned for lacquer, mirror and bronze work, later told me, “The wonderful detailing and restrained lines of the Portaluppi interiors are quite simple, but the finishes make it extraordinary.”

I climbed the stairs, letting my hand sweep the walnut balustrade. The sleeping quarters function as separate apartments, and while the relatively humble bedrooms feel almost spartan, the bathrooms are dazzling. Thick blush-marble slabs create towering stalls for the showers and toilets; luxuriant bathtubs anchor the rooms. “Only in Italy could bathrooms like this be made, with the availability of so much marble,” said Mr. Fincato.

I stayed until the setting sun glinted across the polished floors and distant, celebratory pops of prosecco could be heard from the garden. There would be a private party that evening, and I could almost feel the house’s soul stir back to life. Was I invited? No, but it didn’t matter. I was taking a spark of insight home with me. The magic of the place is in its heady cocktail of materials—mirror, lacquer, stone, leather, metals, glass. I vowed to avoid living the rest of my life surrounded only by old, brown wooden furniture.

As I left, waiters in dinner jackets poured coups at the bar as chic partygoers arrived. “The house feels timeless yet so of its place,” said Ms. Kennedy. “Milan looks austere and unforgiving in a way, but you go through a courtyard door, and a hidden, beautiful world unfolds.”