Lord Norman Foster buys second unit at 912 Fifth Avenue

British starchitect Lord Norman Foster has bought a second unit at white-glove co-op 912 Fifth Avenue, bringing the amount of his total purchases in the building to $13.9 million.

According to city documents, the Pritzker Prize winner and his wife, Lady Elena Foster, closed on unit 8B June 29 for $6.7 million, just two months after purchasing unit 8A for $7.2 million. The couple plans to combine the units into one large floor-through apartment in the luxe pre-war building, which is located between 72nd and 73rd streets, said a source. The seller is listed as Barbara T. Missett.

Foster, who designed the triangular-framed Hearst Tower at 300 West 57th Street, is working on 200 Greenwich Street, a 78-story office tower at the World Trade Center site, and Masdar City, a zero-waste, car-free five-square-mile city in Abu Dhabi.

But several of his firm’s projects have recently faced roadblocks in the uncertain economy, including the now-defunct “Russia Tower” in Moscow, which was to have been the tallest building in Europe before plans were shelved.

Foster was not immediately available for comment.

Foster’s second purchase in the building appears to answer some questions raised when the New York Observer reported that Foster had purchased unit 8A. Brokers wondered why the architect would be interested in a “long and thin” apartment with only two rooms facing Central Park.

Neither unit was officially on the market, though a three-bedroom unit on a lower floor is listed by Stribling & Associates for $5.95 million.

“Those are strong prices,” one broker said of Foster’s purchases at 912 Fifth Avenue. “The luxury market is waking up.”