There are a a couple indications you might require house ventilation, such as:
1. Persistent odors
If you have problems getting intense odors out of your house, you may have a ventilation concern.
2. Stale air
The air in your space should feel fresh, but stuffy areas mean you could have inadequate ventilation.
3. Disproportionate dust
Dust can develop more often in homes with poor air movement.