HVAC south of Canada tends to leave out the V part.
Homes recently built in Canada are indeed so tight that controlled ventilation is needed, almost required, for health of people and pets.
A thoughtful home buyer south of Canada with the funds to make it happen can get her/himself a home built that has the same issues with ventilation that our neighbors to the north have. That is, we must PLAN for the introduction of fresh air to replace the air we exhaust when we
- Turn on a Bathroom light/exhaust
- Turn on a gas/oil furnace
- Turn on a gas water heater
- Operate a clothes dryer
- Operate a range hood
And we want to maintain a positive pressure inside so that when we open a door, outside air is pushed away from the opening, at least briefly, so that pollen/dust/mold spores stay outside.