* Siemens, Adidas, Zalando offices cost hundreds of millions
* Aimed at making firms more open, less hierarchical
* Face-to-face interaction boosts team performance-MIT study
* Investors sceptical about the benefits
By Jens Hack and Emma Thomasson
MUNICH/HERZOGENAURACH, Germany, June 23 (Reuters) - Major German companies are investing in ambitious new buildings designed to attract top staff and encourage innovation, seeking to create a more dynamic corporate culture and keep pace with U.S. rivals despite investor concerns about the cost.
Germany is competing in a global race for top talent, particularly in technology and design, as firms such as Apple and Facebook work on futuristic campuses with gardens, fitness facilities and gourmet restaurants.
Siemens opens new headquarters in downtown Munich on Friday, a move it hopes will help Chief Executive Joe Kaeser's drive to open up the engineering giant founded in 1847 to new ideas, loosen hierarchies and increase staff engagement.
Sportswear firm Adidas and fashion site Zalando are also investing hundreds of millions of euros in new offices in Germany.
Investors have questioned how much glitzy buildings can really help improve performance. Apple's new "spaceship" campus is now well behind schedule and over budget at $5 billon.
After the near collapse of Royal Bank of Scotland in 2008, its new 350 million-pound ($518 million) headquarters was dubbed "Fred's Folly" after disgraced former CEO Fred Goodwin.
Shareholders have also complained about an upgrade of PepsiCo's headquarters, set amid lakes and fountains.
Siemens says it is investing a figure in the "low triple- digit millions" of euros in its building, which collects rainwater to flush toilets and will use 90 percent less electricity and 75 percent less water than its predecessor.
"I remain to be convinced whether this is the best use of shareholders' money. At least Siemens are deploying the most energy-efficient technologies," said Barclays analyst James Stettler.
All three German office projects are introducing open-plan, shared desks, a big change given the country's hierarchical corporate culture in which most managers sit separately from their teams in closed offices.
SITTING WITH THE BOSS
The firms say they are not only trying to save space, but also encourage employees to interact more with each other.
"Our new headquarters is a place where encounters occur," Siemens CEO Kaeser said this week.
A Massachusetts Institute of Technology study found that 35 percent of a team's performance can be predicted by the number and quality of face-to-face interactions its members have.