Plants and tight houses
It is commonly believed that plants improve the air quality of a home by filtering the air, but what about the extra humidity from watering or other humidity sources, such as trays for orchids? Is this an issue and, if so, how do you address it?
Thanks,
Norman
CZ 3A
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Replies
Yes, turning your home into a greenhouse for tropical plants will raise the indoor humidity, which in most cases can be dealt with by a modest uptick in the ventilation rate.
Our pretty small (1700 square feet of conditioned space) and pretty tight (.59ach50) house has half dozen large plants. We've never noticed any moisture issues or felt a need to increase ventilation rate above 72 cfm. It's pretty dry in winter anyway here in Maine. We put the plants outside in the summer.
Norman,
I think there is little risk as long as you don't have a grow room in the basement. With my houseplants, I've noticed they put on very little growth from year-to-year. I recall reading somewhere that poor growth is a side-effect of UV coatings that are included on many modern windows.
Get a dehumidifier in the basement. You will air condition less, too. Instead of running at 72 for instance, you will feel comfy at 74. Get one that works down to the fifty degree plus range. My house is as tight as yours and my central dehumidifier is th best thing I ever did.