Mixed humid climate, conditioned crawl space
I feel like I’ve already asked a lot of questions and many thanks for the responses thus far. I feel like I’ve already poured through a mountain of info as I prepare for this upcoming home construction. Today I started going through the assembly details for the crawlspace. Basically, the land, placement, etc, all dictate the need for a crawl space. I have been considering enclosing my current home’s crawl space and had talked with someone about it a couple years ago (who mentioned using a dehumidifier), but after reading more today I’ve begun to realize the approach to eliminate moisture issues in that space, may not actually do so completely. In the GBA article “Building an Unvented Crawl Space” , dehumidifiers are mentioned for temporary use to remove construction moisture. Even a Lstiburek article  showed a lot of approaches, but no mention of the dehumidifier. I found a couple articles,  below explained its use as an option for example, but preferably without transfer grilles. There seems to be conflicting ideas and neither seems to work fully. If you use a dehumidifier the complaints are the energy use and noise. Without, evidently humidity can still be an issue in the off-seasons Spring and Fall. If using transfer grilles, you are supposedly equalizing the pressure, but exposing the air in the living space to that below, making any effort to ensure a tight seal critical. And if using the supply and return approach (evidently with two transfer grilles to equalize pressure as well), the positive pressure underneath can also work against you.
So in the end, I guess my question is… what is the best approach? Is the need for a dehumidifier over-exaggerated? Or is it likely humidity will continue to be a problem, just not all the time? I even saw in comments recommendations for folks to “monitor” the humidity level. Is that right for new construction? I would hope that if I need one, that I could go ahead and wire for it, yet there doesn’t seem to be a lot of info in this direction. Any help would be much appreciated.
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