Eh, kind of. Builders in the northeast didn’t choose balloon framing because it’s thermally efficient - they just didn’t have alternatives in the same cost rang

Eh, kind of. Builders in the northeast didn’t choose balloon framing because it’s thermally efficient - they just didn’t have alternatives in the same cost range. Many homes in that region were build with masonry claddings as well to increase thermal mass and R value of the wall. The foam sheet insulation you speak of is relatively new to the industry, at least for middle class homes. Having a continuous layer of insulation outside the framing definitely makes stick framing more energy efficient than it would be with traditional fiberglass batt insulation in a wall cavity.