Most all crawl spaces are vented and have the same problems. Until recently, the building codes did not recognize conditioned crawl spaces.
We now have the option of building foundations without crawl space vents and adding dehumidifiers to control temperature and humidity levels.
The conditioned crawl space concept has been around for years; however, with the advancement in technology we have been able to convert old or build new spaces for much less money then just 10 years ago. The attached photo shows what an Aprilaire dehumidifier looks like when installed in a crawl space (this was an attic knee wall crawl space).
If you have moisture issues under your house or in some cases improperly vented attics, you want to have it corrected as soon as possible.
By, Duane Cotton