That’s a laudable goal, Nick. But 3D house printing has been around a long time, and as far as i know no one has made a go of it. I even remember a company in Central America was formed to print houses, they were able to snake the minimal equipment needed to print a house in a day (onto a existing footing) thru narrow winding mountain dirt roads. The Japanese have printed homes, hobbyists have printed homes and toy castles, Israelis have printed homes. The tech, the procedures, the cement mix, are not the problem, sales are the problem. As a for-instance, look to the islands wrecked recently by the twin wallop of hurricanes Irma and Maria. Where’s the wave of fast rebuilding using cheap modern 3D building? Or, look to California, where massive fires are the norm, and everyone knows cement (or concrete) doesn’t burn, yet in whole neighborhoods, every house is burned to the ground there. You don’t even need to print the entire house in a sweep thru fire or hurricane ripped neighborhoods, getting the core required rooms up in a day for bare occupancy is worthwhile. But in 30 years of looking for it, it’s not happening. Naming the machine or system on a 40 year old Radio Shack toy prolly isn’t helping any.
There was even a guy in the Sahara who used a fresnel lense to sinter layers of plain sand into glass to build with. Very slow, but used little equipment, and could have been optomised for speed in various ways. After the one “look what he did!” publicity, nothing happened.