So the Arizona architect decided to build an energy-efficient home on a slope 6,000 feet up. Dubbed Falcon Nest, the chimney-shaped glass-and-steel tower he designed is 124 feet tall.

And that’s where Pal’s seemingly pie-in-the-sky aspirations fell back to Earth.

“It (was) a new concept and cities don’t permit more than 35 feet building height,” he recalled of his dilemma in the 1990s during a video interview with

Pal’s flight of fancy finally landed on the rocky slopes of Thumb Butte — a volcanic formation — just outside Prescott, Ariz., thanks to “loopholes” in city ordinances.

Pal finished construction of the tallest single-family home in North America about 20 years ago. The tower has 10 floors, but technically it’s only three storeys of actual living space, explains Pal, who built the $3-million (U.S.) structure as a home office and residence for himself and his wife.

Occupying a footprint of only 24-by-24 feet on a one-acre lot, Falcon Nest features a 2,000-square-foot glass-enclosed solarium that extends out from the core structure in four directions. The sixth-floor living space consists of two bedrooms, two bathrooms, a kitchen and a great room. A third bedroom and two more bathrooms are on another level.

House Features

The top floors, accessible by stairs, are primarily for the passive solar heating and cooling system. A hydraulic elevator runs to the sixth floor. Observation decks offer 360-degree views of mountains and hundreds of kilometres of Arizona desert.

Using solar energy means the house costs nothing to heat and cool, Pal explains. Windows facing each direction open for cross-ventilation and fans help drive excess heat upward to be siphoned out through the top of the tower. In winter, warm air is trapped and recirculated to heat the home, he says.

The design of the house was partly inspired by his childhood years without air conditioning in hot, humid Kolkata, India, Pal tells the interviewer. He says he looked at 200 sites before finding the right one of solid rock with no cracks.

A fireplace and circular staircase leading to the upper floors are features of the living room.

“It is just resting on the ground … so the ground moves, but the building stays as is.”

While there was some local opposition to the project in the early days, Pal says busloads of tourists visited the site.

“It excited the imagination of the people,” who wondered how he’d pull it off, he says.

But if its completion was a towering achievement, selling the property was an equally tall order.

Pal, by then a widower, listed it in 2015 for $2.8 million, dropping the price to $1.5 million two years later. An auction in 2017 failed to produce a buyer, recalls Frank Aazami of Russ Lyon Sotheby’s International Realty.

The high-end real estate professional, who rose to the sales challenge for almost eight months, says Pal refused several offers of about $1 million.

(From one vantage point, the tower “looks like it’s a fist giving you the finger,” Aazami jokes in an aside.)

Falcon Nest was finally bought for $755,000 last year by vedic astrologer Ernst Wilhelm and his artist wife, Srishti Wilhelm.

“This amazing house, we feel, was built for us, with Ernst being able to focus his telescopes into the heavens from the top, and me having a three-storeys-high art gallery built into the house,” she says.

The numbers

Selling price: $755,000 (U.S.)

Size: 4,362 square feet

Bedrooms: 3

Bathrooms: 4