Construction Physics

For people thinking "pre-fab"/automation is "the answer" to this shortage, I recommend reviewing Brian Potter's blog, Construction Physics.[1] It ain't so simple. Building sites vary a lot, even in the same neighbourhood. Buildings are very complex, and individuated to meet customer demands. Crucially they are low value per unit mass, so transport starts costing more than on-site construction after two hundred kilometres/miles or so. There are multiple morasses of regulations and regulators. 1. https://constructionphysics.substack.com/

> Fixing up homes is very inefficient and usually done by mom and pops. This doesn't ipso-facto make it inefficient. There's evidence that construction does not become meaningfully more efficient with scale [1]. At GIGANTIC scales, you're looking at maybe 10% savings. And these scales are quite rare in the US & the EU - mostly only happening in Asia. True, on the largest investment of most people's lives - 10% is something... Anyway - you're not going to get great returns with layers of high-paid management and beat mom & pops by much. [1] https://constructionphysics.substack.com/p/why-are-there-so-few-econom…

Here is a link to one of the best articles (and set of analyses) I have read on the topic of the US housing shortage from the demand side: https://constructionphysics.substack.com/p/is-there-a-housing-shortage… Land use, rezoning and infrastructure development (and redevelopment) is going to be a couple trillion dollars or more and a whole lot of political fighting.

Their post on mobile homes is worth the time too: https://constructionphysics.substack.com/p/the-rise-and-fall-of-the-mo…

I'll wait to see what Construction Physics[1] says about it. He has covered the prefab space in detail. [1] https://constructionphysics.substack.com/

The Construction Physics blog convinced me it's not all an empty fad, but is clearly plagued by problems currently: https://constructionphysics.substack.com/p/3d-printed-buildings There's also a lot of potential for 3D printing in construction in general. This 3D printed beam idea certainly seems interesting and worth testing out: https://www.minimass.net/

To save everyone a search: https://constructionphysics.substack.com/

This sub stack has some great coverage of those questions: https://constructionphysics.substack.com/p/why-its-hard-to-innovate-in…

The best article I've read about Katerra is still from Construction Physics, it goes into much more technical detail. [1] [1] https://constructionphysics.substack.com/p/another-day-in-katerradise

Transportation costs seem high: > It’s difficult to ship lumber overseas cost effectively: lumber is (or was) one of the least expensive materials on the planet. At $300 per 1000 board feet (the average price over the last 25 years), a 20 foot shipping container holds just $4500 worth of material. The cost of transporting a container across the ocean is $1700 dollars or more. https://constructionphysics.substack.com/p/lumber-price-faq

As an avid reader, I anticipate the feedback as "unlikely to scale, since the centralized productivity gains don't outweigh the diminished flexibility and substantial transport costs". This is a recurring theme with prefab system he analyzes, they scrape by employing labour arbitrage at a cheap production site, but do not unleash the productivity gains we associate with industrial production. This becomes obvious when you look at the distribution of construction costs for a finished building: https://constructionphysics.substack.com/p/construction-cost-breakdown… The most a prefab can hope to achieve is attack maybe 30- 40% of the total costs in that pie chart. You cannot prefab electrics and plumbing, foundation, landscaping, permitting etc. So even if they crush it and get 100% improvement on their products compared to on site build, that's still a 20% at best overall cost improvement. Bit with that comes the risk of a new and unproven system, costly coordination issues that are easy to rectify in the traditional method - but if the wrong prefabs are shipped across the country you are dead for a few weeks, since the next stage cannot start.

From the same Substack: "Homebuilders don’t seem to think the burdens of OSHA and other safety regulations are all that high. Complying with OSHA is the second lowest category of perceived jobsite regulatory costs." https://constructionphysics.substack.com/p/how-much-safer-has-construc…

This is an interesting professional response to the original paper: https://constructionphysics.substack.com/p/roman-vs-modern-concrete

Trades are one of those areas (along with software engineering) where it is relatively easy to be your own boss. The market in general is pretty competitive on both the buyer (lots of individual homeowners needing work done) and seller (lots of small independent contractors selling their labor) sides; that should make overall prices & wages reflect industry-wide (or at least local) supply & demand pretty well. ConstructionPhysics has a pretty good series about why the construction industry never really realized economies of scale the way most other industries do. Even when you have large homebuilders like D.R. Horton, their primary competitive advantage is usually reduced cost of capital, which goes away if capital becomes expensive for everyone. https://constructionphysics.substack.com/p/why-are-there-so-few-econom…

They actually wrote a whole article on dry-wall and theorizing on what the next iteration of it could look like https://constructionphysics.substack.com/p/comparing-process-improveme…

There is a lot of background on nuclear costs. From https://constructionphysics.substack.com/p/why-are-nuclear-power-const… & other sources, I've heard safety standards around radiation were set higher than ever proven necessary, and also ratchet up to obviate any cost gains per unit output.

I recently read Construction Physics' post on concrete use: https://constructionphysics.substack.com/p/so-you-want-to-use-less-con… and I consider it to be required reading for people outside of the field on the topic of concrete emissions. Globally, concrete production emits like crazy but this is largely a product of scale; other building materials emit far more GhGs by mass and volume but are used in much smaller quantities than concrete. I'm all for a broad package of carbon taxes to both reduce growth and force the development of political and financial solutions for a low-growth, steady-state or degrowth economy but don't be misled into thinking the end result is a smaller share of concrete as a building material. More likely, carbon taxes will reduce the proportions of plastics, steel, aluminum and glass in construction in favour of more concrete.

This reminds me of the "designing a house to last 1000 years" article discussed on here earlier in the year, and the many factors that the author considered there. https://constructionphysics.substack.com/p/how-to-design-a-house-to-la…

Also unlike a video game, the tech-tree dependencies are not obvious. We don't know in advance whether a tech will be a productive avenue of R&D, or if it depends on other unrelated advances in theory, material science, or computer modeling, or was actually completely unfeasible in the first place. I find wind power [1] as a case study representative, and we see similar stories for e.g. fusion, cancer research, AI [1] https://constructionphysics.substack.com/p/why-did-we-wait-so-long-for…

>the technology available for building them have improved since then Broadly, construction is the singular industry where productivity hasn't improved with modern technology. https://constructionphysics.substack.com/p/sketch-of-a-theory-of-const…

It may be less important, but still an important consideration. In regards to nuclear costs, most comparisons include projects which were plagued by redesign due to regulatory changes. It is likely that reusing designs will reduce costs significantly [0]. In addition, solar and wind must be paired with energy storage. Once this is done, they become uneconomical in most places. There's a reason that Europe, the most pro-solar/wind polity on the planet, has not been able to get energy independence despite their wealth. The costs for a resilient system are just too high. [0] https://constructionphysics.substack.com/p/why-are-nuclear-power-const…

In more detail than you wanted: https://constructionphysics.substack.com/p/construction-physics-table-…

Might be nitpicking here: Referring to the pie charts under this section[1], I can't help but think images like this are intentionally meant to mislead: [1]https://constructionphysics.substack.com/p/why-are-nuclear-power-const… I understand author picked it from some other source, Dawson 2017 or whatever. These pie charts are not like for like, when it includes the renewables -- maybe the coal/gas/nuclear fine. So why put them next to one another. I can't tell if the costs of renewables are for entire "farms" (solar or wind farms). What about lifetime of plants/farms, total value derived, etc.

Here’s an interesting analysis of shortage: https://constructionphysics.substack.com/p/is-there-a-housing-shortage… I like the comment: “I think one of the problems in this discussion is that the word ‘shortage’ doesn't have a clear meaning. If gas is $6 a gallon, should we say there is a shortage of gas? If I get stuck in traffic on the way to work, can I say there is a shortage of roads? If I have to park 4 blocks away from my apartment, is there a shortage of parking?” And a one-sided view on why your home is not an investment: https://jlcollinsnh.com/2013/05/29/why-your-house-is-a-terrible-invest…

>Using US houses as an example is quite laughable, the energy consumptions of US households is much higher than German ones. It's an extremely heterogeneous dataset, but a cursory analysis does not agree: Germany: 136 kWh/m^2 https://bpie.eu/wp-content/uploads/2018/01/iBROAD_CountryFactsheet_GER… US: 47000 Btu/ft^2 — because we like dumb units — 148 kWh/m^2 https://constructionphysics.substack.com/p/looking-at-energy-use-in-us… That's a slight win for Germany, but it's not by much. For the most part, US houses are simply larger than German ones, which is where that energy use comes from. (US temperatures are also harsher, in both directions.)

Automating house renovation or even house building is a challenge which will take a few decades more. Some trouble of bricklayer automation described in today's HN: https://constructionphysics.substack.com/p/where-are-the-robotic-brick…

Related: https://constructionphysics.substack.com/p/why-its-hard-to-innovate-in…

https://constructionphysics.substack.com/p/folding-at-home Good recent summary on state of foldable construction.

A somewhat less meandering explanation for the modern dominance of balloon framing, which also draws parallels to software development: https://constructionphysics.substack.com/p/balloon-framing-is-worse-is…