Four hundred bricks line Jason Harris’s hallway, and none of them hold the ceiling up. Arranged in an earthy ombre from ruddy terra cotta to cream, these once-functional rectangles are now purely for show. The London-based architect doesn’t think this hefty display lends him much gravitas in British brick collecting circles, though. “I’m a lightweight brick collector because I just like the color and the shapes,” Harris says. “I feel a little bit of a fraud amongst the collecting community.” And he’d definitely be a fraud among builders, since his…