Photo by Danny Fulgencio

Photos by Danny Fulgencio

What is that big angular building high on a hill behind the Belmont Hotel?

For the three years it was under construction, this question came up a lot. The short answer: It’s a house.

More accurately, it is the biggest, most energy efficient home in West Dallas. The house, with its cantilevers and glass walls, has spectacular views of Dallas.

Mary McDermott Cook, chair of the Trinity Trust, decided she wanted to buy the land for her home after having a glass of wine at Bar Belmont one night. She agreed to buy two lots on a handshake with Monte Anderson’s real estate agent.

Late last year, Cook moved from one of the city’s most exclusive addresses, Strait Lane in Preston Hollow, to take up residence in West Dallas.

An advocate for all things Trinity River, she says she believes in the neighborhood.

“I hope it will set a style for the neighborhood,” she says of her new home.

The house, with its central spiral staircase and kitchen the size of a Kings Highway bungalow, is light-years from what was there before.

While it was under construction, the home was nicknamed “dump top” because it previously had been used as an illegal dump. Workers removed more than 100 tires, a motorcycle frame and parts of a hospital bed, among other bulky trash, from the site.

Cook hired Booziotis & Co. Architects to design her home with simplicity and energy efficiency in mind.

Four massive stone pylons define three spaces within the home. One of the three stories is below street grade, keeping the house in scale with its two-story neighbors. Walls of glass define the north and south edges between the pylons, creating a downtown view from every room in the house. From her bedroom, Cook can watch the progress on construction of the Santiago Calatrava-designed bridge named for her mother, Margaret McDermott.

Each window wall has panels that allow cross ventilation. It is designed to be cool in summer and warm in winter.

The home has 8-inch thick concrete walls and high-performance window glass that keeps out heat. Cisterns can collect up to 10,000 gallons of water, so even predicting for future drought, no city water will ever need to be used for landscaping. It also has solar water heaters on the roof.

The flooring is made of bamboo, and the countertops are made of recycled materials, including glass and concrete.

She is seeking LEED certification for the house, which also serves as headquarters for her charity, the Eugene McDermott Foundation.

Why is all this energy efficiency so important?

“Because I believe in it,” Cook says.