Office space in core areas of China's big cities is getting more expensive. But instead of walking away, companies are paying up, topping expectations in China's commercial property sector in an overall weak real estate market.

The demand for grade-A office space in major cities has remained steady, driven by a lack of new supply, low vacancy rates, domestic companies' interest in new leases and increasing confidence on the part of landlords, according to property services consultants and providers.

A glance at a skyscraper in

China World Trade Center Tower III, at 81 stories and one of the tallest buildings in Beijing, is also the most expensive office building in the CBD. It currently is home to about 70 companies.

The banking and insurance industries were the main drivers of demand, and several new leases were signed in the sector.

Domestic companies again accounted for the majority of new leases, while foreign firms generally renewed or leased comparatively smaller spaces.

"Landlords and tenants are becoming more discerning as the market matures, and there is an increasing understanding that not all buildings are created equal," said Eric Hirsch, head of markets for JLL Beijing.

By comparison, most other submarkets were flat or registered minimal increases.

For Zhang Ying, managing director at JLL North China, the rising rents and growing construction areas in the CBD were a sign of something more: signs of the company's expansion in China.

Working for JLL for 18 years, Zhang has witnessed the company's growth from a single office with three people to one having more than 2,000 staff members.

Meanwhile, starting from a 360-square-meter office in Fulllink Plaza in Chaoyang district, the company's Beijing branch represented the first company to move into the China World Trade Center Tower III in 2010.

It now occupies a spacious office on the 11th floor of the landmark building, with a unit size of nearly 3,500 sqm.

During construction, the company stayed in the World Trade Center Tower I from 2003 to 2010.

"The size of our business is 24 times than that of 10 years ago, and the number of employees is 13 times," Zhang said.

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