> Any modern home build likely has an ERV as part of the design

Sounds very country dependent. I really doubt it's true here in the UK. But then, UK housing is just garbage all around unless you build something custom and put a lot of money and attention into it.

> Sounds very country dependent.

Yes, I meant in the US. Apologies for not making that clearer. I don't think ERVs are uncommon in new construction outside the US, but I don't know as much about that.