The 11-unit industrial loft conversion at 1855 North Halsted Street really packs a punch at the roof level. That’s where you’ll find a triplex penthouse with a ton of natural lighting and a network of outdoor decks. The just-listed unit is practically one big conservatory, with walls of windows and an atrium shooting up to a ship-like sloping glass roof.

Developer Lowell Wohlfeil and architect Ron Zriny made it this way when they transformed the former phone company building into luxury lofts in 1978. According to a Chicago Tribune obituary it was the late Wohlfeil’s first major project, a trailblazer on the North Side. It would trigger a rush of similar conversions in Lincoln Park and especially along Halsted.

Kieran Conlon, principle/partner at Conlon Real Estate Co., credits his brother and company founder Sean Conlon with giving the loft its open layout and many of the finishes it has today. Sean owned the unit from 2001-2004, just prior to the current owner.

A gussied-up freight elevator goes to the loft’s fourth floor entrance. The first impression is made at the foot of a three-level floating steel and wood staircase with the atrium above. Just beyond is the great room, running the width of the building north to south with windows above the roofs of neighboring homes and capturing a great deal of skyline. A newer eat-in kitchen claims the south end, a living area with a giant architectural fireplace takes the north, and dining is sandwiched between.

The first stop on the floating staircase is a sizable lofted office—the first candidate for bedroom conversion. At the second full level, a family room with floor-to-ceiling glass walls and a media den (another possible bedroom) lures people to the lower terraces—a beefy northern section connected to a dog run. Literally, that’s how the seller has it set up, with canine access at all times via a dog door in the master suite’s walk-in.

Speaking of the master, it’s a nice one with continued floor-to-ceiling glass, a lounge area, and a glass block-partitioned bathroom. It’s outlined by the terrace’s dog run with no direct human access.

One can reach the third level via outdoor terrace or the main stairs. This part of the home is 100% leisure. A balcony in the sky, your head almost meets the sloping glass roof. There’s a seating nook pressed to the windows, a wet bar behind antique iron doors, and upper terrace all around. This is the prime terrace, with the most open space and biggest views, but Conlon agent Dan Sullivan points to a 10×10 buildable roof area another level up where a massive Chicago flag is being flown. “You can see the lake from up there.”

The home has an equal amount of interior and exterior square footage: roughly 3,000 apiece. These figures don’t include the one-bed/one-bath coach house, cloaked in ivy and primed for guests or renters. The loft is listed as a two-bedroom, but is actually organized as a one-bedroom. It would be among the most expensive one-beds to ever sell in Lincoln Park if the $2.25 million asking price holds. As is, it’s the priciest loft listing currently in the city.

A swap was part of the previous sale, so it’s hard to get an accurate read on the unit’s value in 2004. And it’s definitely hard to find comps. Kieran and Sullivan looked outside Lincoln Park and began marketing the place quietly as a pocket listing. “The seller originally wanted to price it above $3 million,” says Kieran. “We came down after listening to broker feedback.”

The seller has architectural plans for the addition of two more bedrooms, and another full bath (there are currently two). “You probably with have to do some work,” says Kieran. With a place as unusual as this, a degree of reimagining is almost always called for.