Sleep regeneration took whichever was higher, your house bonus or the camp rate. Camping scales with your rank tier while the house ladder is flat, so from tier 2 upward the camp rate simply swallowed the cheaper houses: a tier-3 player who bought a 15/min shack regened at the 78/min camp rate, exactly the same as sleeping outdoors.

The two now add together. Every house beats camping by its full bonus, at every tier, and no existing owner's rate goes down.