The dining room "literally looked like a conference room,” designer Everick Brown recalls with agony. When longtime clients of his-a culture-obsessed British couple with three grown kids-bought a 1955 five-bedroom house in Harrison, New York, he transformed the bad (vast, oddly shaped rooms with white marble floors that gave off a veritable frost) in order to highlight the groovy, midcentury good (ebony paneling, split levels, cobblestone walls).

To warm the place up, Brown first swapped the kitchen with the dining room; with a smaller footprint, the latter now has a convivial feel, while the new cook space has clerestory windows that soar to pine-sheathed, 20-foot-high ceilings. “Imagine walking into that kitchen with all the natural light.

It’s just spectacular,” says Brown, who gut renovated the home alongside architect Rosamund Young. “From a design perspective, it adds dimension-you’re layering in these peaks and valleys,” Brown says. The previous owners, also collectors, left a horde of art books; it was “like being in the stacks of an Ivy League college,” Brown says.

He helped curate the tomes alongside his clients’ own collection, and in the gallery-esque foyer arranged their art for aesthetic diversity, marrying wood carvings with handblown glass, vertical with horizontal.

Brown also layered plants, textiles, and offbeat fixtures to inject life into the serene interiors: a Tibetan rug provides geniality underfoot in the living room, and above the glass table in the dining room, Brown swapped an “austere and cold” chandelier for an oversize, papier-mâché custom piece by artist Patrick Weder.

“It creates texture in the room and makes it sort of dreamy.” Now the home, secreted away on nearly two acres, really feels like a leafy, luxurious piece of paradise. Says Brown, “I started referring to this project as a Shangri-La.”

Living Room

A statement wall is encased in steel with walnut insets to create a “floating credenza” and hide the TV. Daybed: custom Mies van der Rohe, Knoll. Armchairs and sectional: custom, John Charles Designs. Wood table and lamps: Mariani Gardens. Rug: Tufenkian. Glass-and-steel console: Harris Rubin. Side table: Donghia.

Library

The ebony wall panels and floating Plexiglas shelves are original to the home. “Everybody wanted to demo them and I was like, ‘No, you can’t destroy that!’ ” says Brown. Table and leather chairs: custom, Resource Furniture. Bar: custom, Patrick Weder. Rug: custom, The Rug Company. Sofa: custom, Room & Board. Painting (right): The Busy Heart by Shawn Dulaney. Mosaic (left): David Holleman. Artwork (over door): Makenge root wedding basket from Zambia. Glass vase: Aaron Adamson.

Foyer

The entry has the spare, lofty vibe of an art gallery. Bench: Cisco Brothers. Rug: The Caravan Connection. Framed art: antique Chinese ink paintings. Top right shelf: brass figurine from the Democratic Republic of the Congo, R&Y Augousti boxes. Bottom right shelf: vintage vases from Jonathan Adler. Back wall: black-and-tan ceramic bowls and vases, Studio Keramik.

Main Bathroom

“We were looking to create a spa-like environment, a place you could really unwind,” Brown says. Many of the home’s custom pieces, like this vanity, are by Swiss-born, Brooklyn-based artist Patrick Weder. Flooring: Bleu de Savoie limestone tile. Shower: White Plains Glass. Pendants: Lights Up.

Kitchen

Lacquered white upper cabinets “keep it open and airy,” Brown says, and draw the eye up to the breathtaking pitched ceiling. Outer counters: Caesarstone. Island counter: honed Carrara stone. Cabinets: Artcraft Cabinetry, Bilotta Kitchens. Hood and ovens: Miele. Refrigerator: Sub-Zero. Stools: custom Azumi, Design Within Reach.

Dining Room

The previous, “austere” light fixture over the table was replaced by an organic piece with a chicken-wire base. Chandelier: custom, Patrick Weder. Dining table and chairs: custom, Ligne Roset. Rug: Madeline Weinrib. Vases: Eva Ziesel via KleinReid.

Main Bedroom

Bed and ottoman: custom, Cisco Brothers. Sofa: Hampton Serpentine by Vladimir Kagan for Room & Board. Bench: Tucker Robbins. Pendant: Y Lighting. Art: by Lisa Breslow. Window treatments: via Accent on Interiors.