For years, North American building codes have required apartment buildings to have two staircases that can be used as exits in case of a fire. Some housing observers wonder if this has been hindering our ability to build more and varied styles of housing. The B.C. government is now looking into relaxing requirements so that apartments taller than two storeys and, likely, shorter than six storeys can be built with just one staircase as in many European countries. It will spend the next year exploring possible changes to the B.C. Building Code… Seattle has allowed single staircases in multi-family buildings since the late 1970s when it mandated sprinklers. …Urbanarium, a non-profit society made up of architects, landscape architects, planners and other professionals, is launching a contest called “decoding density.” It’s asking people to submit proposals for updating building codes that could improve the design of six-storey-plus wood-frame structures.