If you live in a "tight" home that the builder designed to be energy-efficient, chances are not much air leaks out of the house through cracks and holes around windows, doors and walls.
That's great for saving on your energy bill. But a house that doesn't let your air conditioned air get outside might not let any fresh air get inside, either.
You need fresh air for healthy indoor air quality.One way to push dirty air outside and draw fresh air in is to install an exhaust vent in over your range in the kitchen and exhaust fans in every bathroom. When you turn the fans on, they will rid your indoor air of humidity, odors and smoke.
But they're not enough. You should only run your exhaust fans during your shower and while you're cooking--not all the time. If you run them all the time, they will suck your expensive air conditioned air out of the house, and that's a waste of energy.
A whole-house mechanical ventilation system like a heat-recovery ventilator or an energy-recover ventilator will draw in measured amounts of outdoor air--and cool it off on the way in so your air conditioner doesn't have to work so hard.
Controlling the quality of your indoor air is both possible and smart.