Here are some tips that will not only save you thousands of dollars in home repair, but will also make your homes doors operate safely as they were designed to do. The first thing you need to do is to control your home's humidity level. To do that, purchase an in-home relative humidity chart, as well as a properly sized dehumidifier. You must properly seal the door to prevent moisture and wetness from getting into the wood. The tip here is to stain or varnish all four edges as well as both sides. People rarely seal the bottoms and wonder how the moisture got into the door.
If door hinges become loose, the quickie repair is to install a longer screw. This won't work for long. Instead, you must drill a new and bigger hole into an existing screw hole. To do this, fill the hole using a wooden dowel. Reattach the hinge with a new screw.