“If I offered your listeners a million dollar prize to invent a building material lower quality than drywall that would still pass building code, no one would win the prize. It is literally the crappiest thing we can imagine to build with.”
What's Your Problem? · October 2026
Jacob Goldstein asked how 3D-printing houses in concrete squares with sustainability, given how carbon-intensive cement is. Ballard, whose company prints houses, argues the comparison should be against stick frame and drywall, over the building's whole lifespan and energy use.
Transcript
…mixes for a very narrow set of environmental conditions. And we needed to be able to operate continuously almost in any kind of weather conditions. And so designing that system and all the data and formulation that goes into that was probably the most important breakthrough of the early years.
…is just a small percentage of the actual ingredients in concrete. And so when you think about housing sustainability, there's maybe a few things to think about. One is like, the materials that it's getting about, what's the environmental impact of the materials that you're actually building with?
…like, and then the environmental impacts of operating a building built with those materials, the energy efficiency, the fire rating, wind rating, these kinds of things. So we have worked very hard on our mix itself to reduce the carbon emissions in our formulation of the concrete that we use. Of course, concrete is much longer lasting than a stick frame house in a drywall. Matter of fact, if I offered your listeners a million dollar prize to invent a building material lower quality than drywall that would still pass building code, no one would win the prize. It is literally the crappiest thing we can imagine to build with. So you're already at a low carbon basis relative to conventional construction methods. It's going to last much longer and it is much more energy efficient. That's partly material. It's partly the wall system that we've engineered that there's no thermal bridging inside the wall system. We have a You have like an exterior bead, an interior bead, and then we're careful to make sure that those who…
How many houses have you built? Where are you in the world now?
We are, let's see, sneaking up on 260 somewhere this week. We're always out in the field. We're over 250. We'll be sneaking up on 300 or so by the end of the year and growing very rapidly.
So 300 isn't scale yet, right? I mean, I know it's a lot, and not to belittle the work that you have done. No. But it's 300 more houses than I have built. But it's not like a meaningful number in the context of even Texas, right? Much less the United States.
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