As the trees grow bare and temperatures plummet, one needs as many reminders as possible that winter will not last indefinitely. A recent British arrival to SoHo is just the thing to keep these dreams alive.

Marston & Langinger, a celebrated London design firm and retail shop that cemented its reputation building glass houses and conservatories for clients across the U.K. and abroad, opened its first American store on Mercer Street in September. The inviting retail space, filled with home furniture and accessories such as gardening pots, candelabras, mirrors, and credenzas, also houses the offices for the design staff, which, if one is lucky enough to have the space, will create a glass addition to your home that allows you to enjoy the view (if not the sun) year-round.

Peter Marston, now 56, launched the business in 1978, in Norfolk in the east of England, where the company’s factory remains. (He opened a retail shop selling garden furniture and accessories in the Pimlico neighborhood of London about 15 years ago.) “I had always been interested in beautifully made things,” Mr. Marston said by telephone from England. Trained in architecture and furniture design, Mr. Marston was making furniture and doing restoration work on historic houses when he decided that these grand residences often lacked a crucial element. “The front of the house was beautiful, but the back often dark, inefficient, imperfect,” he said. “I loved glass buildings; I always did. We quickly realized that even in an English Cotswold house, this was the thing that was missing.”

Mr. Marston and his partners began designing glass and wood structures that could function as both living spaces and garden showcases, bridging the gap between the house and the surrounding outdoors. “We realized if we made them comfortable rooms, if we brought the garden inside, people would use them. It’s not about the soft furnishings, but the design,” he said. “In a sense it’s quite modern. We’re just trying to create a room with a view,” he said with a laugh.

To that end, Marston & Langinger have built a wide variety of additions through the years, from small glass structures on London townhouses to a wraparound conservatory for a farmhouse in Michigan to projects in Buenos Aires and Tokyo. (Such structures run from about $50,000 to $500,000.) “You don’t need much space,” Mr. Marston explained, “just a couple of feet can lighten it up and make all the difference in the world.”

He spoke of one project, a narrow London townhouse occupied by the owner of Crabtree & Evelyn. It housed a small garden out back, which got very little light. Marston & Langinger designed a two-story glass addition, boasting a living room on the first floor and an airy conservatory above, with a balcony overlooking the garden. “It was a dark space,” Mr. Marston said. “We had no more than 15, 20 feet out back, but we were able to lift it up and lighten it.”

As such, Mr. Marston considers these structures to be more than simply add-ons. “We actually fix houses,” he said. “The space is transformed.”

Of course, not everyone has a house, brownstone, or rooftop upon which to build a glass structure of one’s own. But as Mr. Marston says, “If you can’t have the building, you can still have the accessories.” At the Marston & Langinger retail shop in SoHo, a variety of planting containers are always in stock, as are more unusual items such as antique garden tools and small pieces of Gothic English “ruins,” worn stones covered in lichen and moss ($200-$500).

The retail space also carries a mix-and-match collection of 18th- and 19th-century china in a variety of patterns, with individual pieces such as teacups that make for lovely gifts ($40-$400). The furniture and accessories on offer display an eclectic mix of styles, from a country-style recycled teak cupboard with sliding glass doors ($2,680) to an oval mirror with intricate lace wirework ($1,925) to a 19th-century whiskey barrel ($330). Marston & Langinger also stocks a serious lighting section, particularly important for these long wintry nights, including beautifully delicate Venetian glass hanging lanterns ($460), beaded glass chandeliers ($410), and a variety of candelabras and hurricane lamps ($45-$130).

Marston & Langinger is considering plans to open outlets in Los Angeles, Boston, and Chicago, but Mr. Marston said New York will always remain its flagship store in America. “It’s rather like London,” he said. “It’s a city that everyone goes to. I mean, we could have opened up shop in Greenwich, Conn., but everyone comes to New York.”

Marston & Langinger, 117 Mercer St., 212-965-0434.