Goldilocks Effect?

      Seems that advances in building science have brought us to a question, how much is too much? I, for a long time, have advocated reducing infiltration to a minimum. Homes can't be too tight. I still believe that. However, I am seeing air tightness as a potential hazard when occupants get involved. Most of my clients who buy into "Make it tight, Ventilate right" are willing to be "involved" with their dwelling's operation. Unfortunately they are few and far between! Truly, if we are to be successful, a home is self sufficient; caring for its dwellers without them having to be monitoring and adjusting their environment to meet lifestyle and climate needs. That is the home's job.
     Pressure differentials with reference to the outside and humidity have to be controlled by an adaptive, user-friendly Ventilation system. In Tennessee we have a wide range of seasonal conditions, warm, cold, wet, dry at any day year round. Zone 4 is one of the most difficult environments to get right. So here's a list:
1.) Thermal comfort.
2.) Humidity control.
3.) Changing Pressure differentials with reference to outside.
4.) Efficiency.
5.) Simplicity of operation.
     Retrofit or new construction the goal is optimizing these 5 targets with a minimum of owner involvement. Set the controls and live happily ever after in a healthy, comfortable, efficient home, right? Sounds perfect. Trick is, every home has different requirements. One family of five with 2 dogs, an aquarium, house plants and a busy kitchen will not be comfortable in a home commissioned to accommodate a retired couple gone 6 months of the year to their mountain cabin. I typically provide a year's service to help find the "Goldlocks" setting for a given family. What happens to that home when it gets sold? Who helps new owners adapt to their "Used" green home? I have no answer for this other than it will be a business plan as more and more tight, efficient homes populate the market. In my world it is called continuous commissioning.
       The take away is that high performance homes won't stay that way by themselves, they need tuning and maintenance over their life cycle, fulfilling the needs of their occupants. Can it be done with a Thermostat? I don't believe so.