It's a duplex

I recently wandered into the Sunset Ridge subdivision to see how the new building under construction was progressing, and was surprised to see it was a duplex. I should not have been surprised. The foundation was very large, probably too large to be a one-family house.
Meanwhile the building trades class from the high school is making progress on their house. Last week they were building the forms for concrete.
And on Tuesday they had concrete poured.
I am pretty sure this one will only be a single family house.