If a home layout is smart, it includes space for ductwork and HVAC equipment, and two huge spaces that make it very simple are an encapsulated attic or crawlspace. You'll see lots of conditioned attics on the biggest builder channel on YouTube, but I don't think it's because they're better than crawlspaces- in fact, I'm pitching this to Matt Risinger @buildshow directly, and we'll see if he and the rest of my audience agrees.
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