The intent of this credit is to control indoor moisture levels to provide comfort, reduce the risk of mold, and increase the durability of the home. That would be three very important objectives! Who would want a moldy, uncomfortable home that falls apart? Not I. We should pay attention to this credit.
The requirement is simply to install dehumidification equipment with sufficient latent capacity to maintain relative humidity at or below 60%. We can accomplish this by either adding additional systems or equipping a central HVAC system with additional controls to operate in dehumidification mode. Since we live in Minneapolis — where it gets very dry in the winter and very humid in the summer — our builder was definitely paying attention to controlling indoor humidity levels. (The LEED for Homes Reference Manual does recognize that dehumidification may not be worthwhile for every project.)
We have a VMB-HW Series Variable Speed 4-Pipe Hydronic Fan Coil air handler made by First Co. That title alone should qualify! One of its features is:
Better humidity control – The VMB-HW is designed to extract much more moisture from the air than a conventional system by slowing the airflow over the cooling oil. The result is an improved summer comfort level at higher indoor temperatures.
That’s right! We also have a Honeywell VisionPRO IAQ programmable thermostat that allows us to control the humidity levels in the home. While I’m not sure if you can even have one of these things without the other, I am sure that both together meet this requirement and give us one point.
Did we pay more for this point? I would say we paid more to have a comfortable, mold-free, durable home — something we desired regardless of the LEED point available here. But I am glad to pick up an extra point for doing what we normally would have done.
Indoor Environmental Quality points so far: 1
Cumulative points: 71.5
Additional points needed to get to Gold: 16.5