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Relatively tight house or not

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Maybe this post should go in a forum more related to building science, not sure. On the subject of living in a near air tight house or "zip lock" bag; I think the tightness of the house depends on your average dew point or seasonal dew point. In other words, the location of your home could matter. In an area of the country with summer time dew point averaging 75 degrees or higher, having a leaky house is difficult to make comfortable with low energy costs, unless you have enough solar electric for cooling and de-humidification. In winter time the dew point is usually lower, but not always. It can be 40 degrees, raining, and the inside RH very high. If I have a leaky house or one with high infiltration, I'm not comfortable inside unless I run heat and AC (or de-humidifier) at the same time. The dew point during this sort of weather is too high inside with heat only.

During summer, I believe a super insulated house with controlled infiltration is easier to make more comfortable. More comfort from inside temperature 78F or so and relative humidity (RH) 40 to 50%. Dew point is a better indicator of comfort to me. I can tolerate high desert type heat with very low RH better than lower temperatures with higher RH. I have lived in the Arizona, New Mexico, Colorado, and Montana arid regions and found them all more comfortable than anything east of central USA. I've met some that prefer the high RH.

Now if I use a RMH for heating during winter time and have it use inside make-up air for the burn, then I need high (or enough) infiltration. This gives me fresh air that is good for me, but I suspect the RH (or dew point) will be outside my comfort range. The fresh air brought in by the RMH will be humid air. Then in summer time when the dew point is even higher and I run my AC, I will use a lot of KWH to be comfortable. There's probably many solutions. I could move from the southeast back to Montana or Colorado. I could tighten our existing house and use controlled infiltration. Maybe this would lower KWH usage or maybe not. Higher infiltration gives better air to breath, but comfort will likely be less and during summer cooling months and the electric company has higher profits.

Modern air exchange units do not use a lot of power. They recover some energy, but maybe not enough to matter much. Some folks with tight houses use a small fan to bring in fresh air which creates a slight positive pressure. Some open a few windows slightly. A super insulated home does not have to be built with toxic building materials; however, most are.

Living in the Rocky Mountains with typical low dew point, no need for cooling during summer, heating with RMH, relatively high infiltration is probably a good thing. I lived in Paradise Valley while in Montana and the wind would sometimes blow everyday for a month with wind gusts in excess of 100mph. It was easy to get plenty of fresh air inside the house.

So, what is the best solution for comfort (RH about 40%) in a hot and humid place where you need heat during winter and AC during summer, while providing some clean air to breath and minimize utility bills?
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