The state of Mark Grattan’s apartment is nothing like the high-polish spaces he’s designed and that have been featured in the pages (and on the covers) of glossy shelter bibles like Elle Décor. Instead, it’s an active construction site, covered in dust from constant sanding, with delivery boxes, loose appliances, and building tools scattered everywhere. A hard hat seems almost required. In a few months, though, this nearly 750-square-foot penthouse in a Brooklyn brownstone will be transformed into Grattan’s first live-in showroom — an interior fantasy featuring a library entirely decked out in leopard print, a “green room” with lacquered shelving, adining room with a large marquetry dining table, and a striking red bathroom (“The bathtub is glazed red,” he notes). The current chaos doesn’t faze Grattan. The workshop — and, by extension, construction and manual labor — is his happy place. Growing up in Cleveland, Ohio, as the son of a hobby builder, Grattan has been keenly aware from an early age of what two hands could create. His and his sister’s childhood bedrooms were furnished entirely with pieces made by their father, who also built a deck that “wrapped around the whole entire house.” And in an era when most designers rely on 3D CAD programs or even AI, Grattan is a self-professed workshop junkie, spending hours in his Sunset Park woodshop perfecting his designs. You’d never guess such a hands-on approach from the final pieces; in photographs, his work, with its geometric precision and polished finishes, could easily be mistaken for digital renderings. Before moving back to New York in 2022, Grattan spent six years in Mexico City, where he still keeps an apartment. There, he first taught himself upholstery, starting with leather and later expanding into textiles. (His favorite is velvet.) It’s only fitting that beginning this summer, Grattan is launching Layered, his first collection of textiles with the American textile company HBF Textiles.