What kinds of ventilation equipment are available?
Ventilation equipment falls into two basic categories: exhaust and balanced systems. Bath fans and kitchen-range hoods are almost always exhaust fans. When they blow stale, polluted air outdoors, the house becomes slightly depressurized, and an equal volume of make-up air enters somewhere else. If you have a loosely built house, the make-up air will enter through the cracks or deliberate openings. You can also use an exhaust fan for general ventilation. Balanced ventilation systems use two fans—one to blow fresh air indoors and one to blow stale air outdoors. As long as the airflows are equal, this approach neither pressurizes nor depressurizes the house. The incoming and outgoing air is often ducted to different rooms. Because this approach requires two fans, the equipment can be more expensive to purchase and operate. However, it can give you the most control and provide better distribution of the air. There’s a specialized type of balanced ventilator that’s become popular. It’s call
