Don't Forget the V

I recently spent some time in Hawaii and noticed that many buildings, both residential and commercial, had no heating or cooling systems. Instead, many only had provisions for ventilation. You see, the temperature in Hawaii rarely gets too far out of the comfort zone, so they condition through ventilation. Now to be sure, there were certainly times when I wished where I was staying at least had a dehumidifier, but the temperature was never an issue. Larger commercial buildings did have air conditioning, but smaller stores usually did not. All  buildings had lots of provision for letting the outside air in.

Hawaiian Air Conditioning

In talking about HVAC we often forget to spend any time discussing the V – ventilation. Even if your building has heating and air conditioning, some amount of ventilation is necessary to maintain healthy comfort conditions. The more people and activities you have inside, the more ventilation you need. Most commercial buildings with large central ducted systems have the ventilation built into the duct system. Another common arrangement is to have a dedicated ventilation system whose only purpose is to pull in ventilation air from outside and expel stale air from inside. These systems are often used for buildings which do not have centrally ducted systems. For example, a building which uses VRF systems to heat and cool often have dedicated ventilation systems.

For years residential buildings have depended upon infiltration to provide ventilation. With increasingly tight houses, this method is becoming unworkable. Even for leaky houses this is far from ideal because  you don’t have any control over how much “fresh” air leaks into your house, or where it is coming from. Some may be coming in through your fireplace or crawlspace. In that case, it may not be very “fresh.”

Residential ventilation systems are now available that allow you to control the amount of outside air entering your house. By adding the outside air into your duct system, you can also control where it enters. Another benefit to adding outside air purposefully with a ventilation system is that it can be filtered and conditioned before entering the living space. I encourage you to think a little more about the V in HVAC. You might find it to be a breath of fresh air.