A few thoughts.
- I spent most of my childhood in a new manufactured home. For us it was enough to open the windows in the evening, close them around 10AM, and in the afternoon use the ventilation system to blow cooler (but not cooled) air up from the crawlspace. In homes I've lived in since (in the same climate) this would be completely impossible. Why? Because homes built on-site decades ago are so much less airtight/well-insulated than a manufactured home. This seems ironic given how much cheaper manufactured homes look / their underclass cultural connotations. Are new site-built houses closer to older site-built houses or new manufactured homes?
- It's my understanding that apartment living is, broadly, lower-emissions than detached single family homes. But I live more than 15 floors up in a new condo building and we have to run AC in the winter to keep it below 74F, just because heat rises. This seems like madness.
- Mostly in Seattle, AC has historically been a little silly / unnecessary. This has changed with wildfires. I'm willing to say we should all try to figure out how to deal with higher room temperature and build buildings differently and etc. etc. etc. but particulates in the air mean you can't rely on natural air exchange. I recognize this seems like a corner case but... oof.