I designed and installed a heat-recovery ventilation system in an Alaska house (new construction). I was aiming for five-star or five-star-plus rating but ther

I designed and installed a heat-recovery ventilation system in an Alaska house (new construction). I was aiming for five-star or five-star-plus rating but there was enough leakage that it only got four-star-plus. Still nothing to scoff at compared to the standard contiguous U.S. houses, but the amount of sealing at joints, electrical/plumbing penetrations, HVAC, and vapor barriers was pretty intense. Even the seal under the front door can be enough to lose a rating point if it's bad. Balancing the HRV was done by some professionals once the install was done, and only required a manometer to adjust some wall vents and a baffle in the exhaust duct, which wasn't quite the same as heating/cooling calculations would be, since heating was hydronic and AC isn't really a thing in AK.