Zhang Yue, president of China's Broad Industrial Group, explains the concept of "Vertical City".[Xinhua]

Energy-saving construction firm says its new community design project will include the world's second-tallest building, Li Xinzhu reports.

Vertical City is the latest solution being offered by China's Broad Industrial Group in response to the land shortages that major Asian cities are facing given their high rates of urbanization.

The project, which is still in a conceptual stage, has people live, work and spend their spare time under one roof in a "mixed-community building", said Zhang Yue, the group's president, at a conference on Oct 24 aimed at collecting bids for designing the futuristic city.

"The value of 'Vertical City' lies in its being able to reduce the pressure of the city's congestion, as well as saving energy, reducing air pollution and freeing up land," Zhang said.

"It will also help shorten the time we spend on the way to work and improve our quality of life."

The 200-storey (600-meter-high) building is expected to rank as the world's second-tallest building after the Burj Khalifa skyscraper in Dubai (828m) when it is completed.

At the moment it stands as a 15-storey demo building in Broad's lab, with a total area of 10,000 square meters, as the group sifts through bids from various cities around the world.

"We are very confident this will work because we've conducted a lot of experiments and we expect to complete construction by next year," said Zhang, who declined to name the candidate cities.

The building, which uses a new construction material and a basic steel structure, will be able to accommodate up to 110,000 people at a time. The structure can be factory-produced within four months, and the whole installation can be finished in two months, he said.

Waste material will be reduced to a minimum, while a specially designed exterior wall made from recycled materials will help preserve the building's core temperature, he added.

"We aim to build a people-oriented construction, so we tend to abandon anything that is not concerned with comfort and safety," Zhang said. "This means we can make the best use of space, and trim our costs to 7,000 yuan to 8,000 yuan per square meter."

The company then adds its profit margin and sells its properties for around 10,000 yuan per sq m - or about half the price of properties in Shanghai outside the city center.

"People on lower incomes should have the ability to purchase houses from us because we have various building sizes," he said.

Broad famously built its pavilion in the Puxi side of the Expo Garden within 24 hours to show the public its innovations in construction. The pavilion has passed the highest national test for earthquake-resistance. Broad has also supplied many other buildings on the site with energy-saving air-con units.