Often you hear of the Russian “new rich” who’ve accumulated wealth through corruption or usurping some power. So it was refreshing to read this Bloomberg piece on Sergey Kolesnikov and Igor Rybakov, who built a multi-billion dollar roofing business in Russia. What’s amazing is that they were actually enrolled at the Moscow Institute of Physics and Technology, one of Russia’s top research universities, and worked in roofing as a side business/project.

The roofing degree paid off. Closely held Technonicol, the company they founded while in college, is now the country’s largest roofing-supply company, with a network of 700 distribution outlets across the country, 180 of them wholly-owned. The business had revenue of 59.4 billion rubles ($1.9 billion) in 2012, up 25 percent from the prior year, according to financial statements provided by Kolesnikov.

The company is valued at $2.8 billion, according to data compiled by Bloomberg, making the equal partners two of the youngest billionaires in Russia. Neither has appeared on an international wealth ranking.

“I always liked to solve puzzles, and to me business is a kind of puzzle,” Kolesnikov said. “Neither of us ever thought about earning money of such scale.”

The billionaires, both 41, had a well-timed entry into the market, catching the start of a wave of private homeownership and government upgrades to Soviet-era housing. The number of newly built private homes in Russia almost doubled to 205,000 from 2002 to 2012, according to data from the Federal State Statistics Service, and new apartment units increased more than two times during the past decade to 838,000.

Here’s how they got their business off the ground:

In 1995, four years after the fall of the Soviet Union, Kolesnikov and Rybakov used $40,000 in savings and debt to buy their first plant, a roofing factory complex constructed in 1918 in Vyborg, a city 75 miles northwest of St. Petersburg. They spent $15 million modernizing the facility, and have since built 36 more plants — 30 in Russia, three in Ukraine, and one in Belarus, Lithuania and the Czech Republic.

Important to note their casual culture:

Kolesnikov adheres to western and Japanese management philosophies and quotes management consultant William Edwards Deming, whose statistical theories are credited with inspiring the economic growth surge in Japan after World War II. When Kolesnikov visits Technonicol’s plants, he hands out copies of “The Toyota Way,” a book about the Tokyo-based carmaker’s principles for continuous improvement and respect for workers.

Rybakov, who declined to be interviewed for this story, uses a YouTube channel to post videos of his family on yachting and skiing excursions.

The company maintains an informal corporate culture. It publishes an annual swimsuit calendar featuring female workers. To celebrate the company’s 20th anniversary last December, the billionaires hired a heavy-metal band to record a rock song and created a music video starring Technonicol employees singing in the studio after a day of answering phones and eyeing the clock before grabbing their coats and dashing from the office…

Great story.