As far as I remember first time I saw house 3d printer was with Enrico Dinis D-shape.
PDF presentation:
http://www.d-shape.com/d_shape_presentation.pdf
... some CNC sites named it the house CNC router: http://www.bg-cnc.com/wordpress/?p=592
But even in earlier times, 1940ies, machines existed to make houses by direct deposit of cement mixture. Sure, they used big cement mold but it was probably the birth of an idea.
Source:
http://www.citylab.com/tech/2015/08/this-1940s-house-building-machine-was-the-original-3-d-printer/400967/