We have made huge improvements over the past 10 years on our homes making them “airtight”. Every house leaks some air, the question is how much air does the home leak? A leaky house uses more energy because the air from outside needs to be conditioned (warmed in the winter and cooled in the summer) by the HVAC system.
The problem with a house that does not leak much is that the air in the house can become stale and actually contaminated and unhealthy.
Here is a Panasonic Intelli-Balance ERV 100 FV-10VEC1 we installed.