Cost to Build a Duplex

Hi Carl, I was wondering if you could comment on the cost to build comparison between a twin (duplex) per sq ft vs. a single family house per sq ft.For instance, a 2-story, 3,200 sq ft single family house should be cheaper to build per sq ft than a 1600 single family house with the same quality standards, So, I'm curious how the overall cost per sq ft would compare if a 3200 single family house