Office renovations are all the rage. But while exterior revamps may excite those walking by, it's what a firm fixes on the inside that really matters, says First Potomac's Ernie Jarvis (middle, with the Ezra Co's Glenn Meltzer and CBRE's Manny Fitzgerald). Take 440 First St near Union Station, which First Potomac bought in 2011 and recently renovated. Re-skinning the building—and adding two floors—was important, but Ernie tells us building in high ceilings (8.8 feet) as well as the District's first dedicated outdoor air system (DOAS), which refreshes the property's air every 43 minutes, was equally as big in locking down new tenants. It's worked—First Potomac just signed Alliance Defending Freedom to a full-floor, 15k SF lease, and the LEED Platinum building is up to 45% leased after delivering late last year. The firm is also planning a full floor of high quality spec suites, he says.