This Carroll Gardens townhouse proves that historic preservation and modern sustainability are anything but mutually exclusive.

To sidewalk passersby, the red brick row house at 409 Sackett Street projects the demure good looks you’d expect to find on a leafy block of Brownstone Brooklyn, appearing every bit authentic to its 1899 vintage. But like with many things in New York City, perception isn’t always reality. One might never guess this five-bedroom, single-family stunner is, in fact, a cutting edge certified passive residence — with the receipts to prove it.

Fresh from a thoughtful reimagining, 409 Sackett offers modern living in a timeless package, contextualizing the elegance of its past in present-tense. Behind the renovation was Michael Ingui of Ingui Architecture, a team that couldn’t be more qualified for the job. The Manhattan-based practice, founded by Ben Baxt more than 45 years ago, has a longstanding reputation for reinvigorating storied townhouses, including the one where Truman Capote penned Breakfast at Tiffanys. Brooklyn-based BZJ Construction led the work, which added a two story extension to the home’s rear elevation. The historic portion of the structure received new mechanicals, framing, floors, doors, and windows. A state of the art Energy Recovery Ventilator (ERV) system, which runs 24 hours a day, filters all air coming into and out of the home for healthy, sustainable living.

409 Sackett checks all the curb appeal boxes. The restored exterior, with its classic stoop, new ironwork, and original cornice, makes a strong first impression — a fitting threshold for a grand entrance to the home’s parlor level. Once inside, you’ll be greeted by an open expanse of sun-splashed living and dining space with herringbone oak floors. The statement kitchen, accented in brecciated Crazy Horse marble from Colorado, showcases premium custom wood cabinetry and a full suite of top-shelf appliances from Miele, Wolf, and Sub-Zero, including two wine fridges. Glass doors reveal a Juliet balcony over the landscaped backyard, accessed from the great room downstairs. The latter is reached both via the skylit main staircase and a second one spiraling down from the kitchen, the perfect shortcut for grilling endeavors and patio dining. Also on this floor are a powder room with a Belvedere Leather quartzite counter and a conveniently located coat closet.

The garden level, where you’ll find the aforementioned great room, offers seamless indoor-outdoor flow to the yard. It has a single bedroom and a marble bath, making for dreamy and private guest quarters. Typical of New York townhouses, it also has a street entrance under the front steps.

Ascend the curving mahogany staircase to the full-floor primary suite, replete with a garden-facing terrace, massive dressing room, and an adjacent sitting room/nursery. The indulgent five-fixture spa bath boasts southern exposure windows, a deep soaking tub, and a spacious shower clad in Rosa Aurora Macchia Vecchia marble.

Upstairs, the third level holds the laundry room and two bedrooms with en suite baths, one with sage and aquamarine theme tile while the other offers a palette of white and “Water’s Edge” colored glass.

While 409 Sackett could sell on form alone, the benefits of its functional specifications can’t be understated. Earning its ‘Certified Passive House’ seal with high performance triple-pane windows, mega-efficient heating and cooling, and constant clean air filtration, the entire structure is effectively sealed from dust, moisture, and pests. That means more comfort and lower utility bills, not to mention a reduced carbon footprint the planet will thank you for. The home’s various systems are mostly contained in a mechanical room in the cellar, which was excavated for added square footage — it’s fully integrated into the home, with a family room and generous closet space.

Tucked between Smith and Hoyt Streets, this coveted address puts you right at the heart of Carroll Gardens, meaning the best of Brooklyn is never far out your front door. Black Mountain Wine House, with its cozy fireplace and rustic Adirondack chairs, is right around the corner. Catch the F or G train at the Carroll Street, just a few short blocks away. Stroll up Smith for Malai Ice Cream (try the saffron pistachio), or kick back in the shade at Carroll Park with your latest read from Books of Wonder. From here, you can even await your Lucali call-back at home. If that isn’t a flex, we don’t know what is.