<So, often plumbing, electrical, and HVAC just punch through the walls to outside equipment, plumbing, and conduit.>

That's true for commercial bldgs, but almost all home dwellings in America with slab foundations have the plumbing and some hvac lines inside the slab. Repairing water and sewer lines in these homes is very expensive.

If I understand correctly from my neighbors’ experiences, they just cut up your walls and put new pipes in there and in the attic when the time comes that you inevitably develop a slab leak. it seems like this is probably a case where it has plenty of advantages for the first owner/1st 30 years (pipes neatly out of sight on the first floor) and when it eventually fails, it will be someone else’s problem besides the original builder or even original owner in most cases. Maybe this has changed in recent years though with the switch from copper to PEX, idk if they can just put that in the slab.

In New Zealand PVC pipes are used in concrete slabs for sewage, which in theory should last something like 75+ years. Water, I think, is still put in the dry wall cavity.

That's correct for water lines, and is expensive. But drain and sewer lines are in the slab. Just imagine the cost of removing your tile flooring, then cutting up the slab, removing the usually copper drain line (on older homes), laying new PVC, back filling with sand or gravel, THEN recovering the floors. Carpet would be a little cheaper.

Doesn't that just imply that a concrete home would have this problem everywhere, instead of just in the foundation?

You could do what they do in larger US buildings. Non load bearing walls are not made of concrete so vertical pipes go into those walls and are encased in drywall. Bathrooms and so on have their horizontal pipes below the ceiling of the space underneath, covered by drywall, so just need to punch a single hole in the concrete floor per pipe.

> If you lay pipes inside concrete, they're really hard to maintain.

I'd like to introduce you to a magical invention... it's called "ducts" :-)

You can have them behind walls, above ceilings, between rooms, between housing units etc. Of course, if the building was not build with maintenance in mind, or neglected to consider future potential needs (e.g. HVAC not catered to in buildings from the early 20th century) - then you have to run things on the outside; but even in those cases, new external ducts can often be constructed, using concrete or other materials (e.g. metal frames and whatever you like as cover, e.g. cement-board, sheet metal etc.)

Yes, you can, but people don't like it. There's classic Wiremold, but put that in a house and the value drops. There is an exposed plumbing as an aesthetic thing, but it's not popular.[1]

[1] https://www.graana.com/blog/concealed-vs-exposed-plumbing-di...

Didn’t know that was a thing. I love it.

The link gives me:

"The owner of this website (www.graana.com) has banned the country or region your IP address is in (IL) from accessing this website."

I guess maybe it's a protest against that genocidal war the government here is waging on Gaza.

Sure, if you were smart enough to have… all your ducts in a row. Ahem

In Latin America hollow brick is often used for walls. I'm not in the construction business, but I'm guessing it has to do with cost, insulation, and the ease of breaking in a crevice to lay conduit lines.

If you want to install a line and there isn't a pre-existing conduit in the wall, you do have to chisel one in. It's definitely more effort than with a "hollow" wooden wall, but it's not terribly bad.

> Look at small low-cost housing in Asia. Mini-split air conditioners and pipes all over the exterior.

I'd attribute this to the "low-cost", not necessarily the "brick/concrete". I'd imagine in the USA houses would be pre-fitted with more conduit, and homeowners could afford the installation of more as needed.