I thought we were at the end of the heating season, but I've got below-freezing temperatures this morning and my parents in New York are getting dumped on with more snow. So let's just say it's near the end of the heating season, when floors should be near their driest.
I saw two floors this week where the winter dryness revealed two different problems. The first was a floor I looked at last fall that was cupped. Indications were that the floor was installed too dry, but the crawl space was a little wet. So I didn't know how much correction we could make by drying the house out. Well, now things are nice and dry, and the floor is still badly cupped. Economically, we can't get the house much dryer or hold it that way all year. So the floors need fixing. And the crawl space needs fixing so the moisture levels don't get out of hand next summer.
The other house had a complaint about gaps that were primarily in a closet. In this case, the complaint was that the HVAC contractor made the crawl space too dry, and that resulted in the gaps. These floors were crowned throughout, with some gaps. The gaps were bigger in the master bedroom closet. The crawl space was sealed, with a dehumidifier. But the wood in the crawl space was still wetter than the hardwood floor. And the sealed crawl space had been in place for three winters now. Granted it was a cold, dry winter here, and gaps might be a little bigger than normal. But the crawl space is wetter than inside the house, and the hardwood was still in the 7% range. What's that tell you? It tells me these floors were sanded in a swollen, cupped condition, and have subsequently dried to near normal levels. It tells me that someone other than the HVAC contractor messed up.