Like a concrete aircraft carrier: was LA’s giant new $724m gallery really worth all the carbon emissions?

Built on tar swamps and two tortuous decades in the making, Lacma’s latest addition used twice as much metal as the Eiffel Tower. How did America supersize revered architect Peter Zumthor?Driving down the palm-lined strip of Wilshire Boulevard in Los Angeles, a striking new crossing heaves into view. A ribbon of glass leaps over the road, sandwiched between two gigantic planes of concrete. As you get closer, the bridge swells out in sinuous arcs, swooping back on itself to inscribe an amoebic, shape-shifting blob, spreading out like an inkblot. From some angles it has a retro-futuristic air, recalling a Jetsons airport terminal, or one of California’s “Googie” style gas stations. From others, the curving roof looks like a great big tongue, flaring out to give the neighbours a raspy lick. This concrete colossus is home to the new David Geffen Galleries of the Los Angeles County Museum of Art (Lacma), a $724m mothership designed by the fabled Swiss architect Peter Zumthor. It is