Wood is a material that is constantly moving. If you have a solid wood door or drawer in your house, chances are that it will be a little sticky during the summer months and work effortlessly in the winter months. This is because the wood expands in higher humidity and in the case of a door, fills the space between the jambs, causing it to stick.
The fix is quite simple. It should be very apparent where the door is rubbing. You will see rub marks on either the door or the frame. Mark the rubbed area on the door with a pencil to easily identify the area.
Now it is as simple as removing that little bit of wood to stop the door from sticking. I typically use a hand plane because I’m very comfortable with using hand tools. You could also use a belt sander, but I advise you to go lightly with it. A belt sander can remove a lot of material in a short amount of time. You will want to remove only the bare minimum of material. Once you have removed the pencil marks, test the door to see if it sticks. If it still sticks, repeat the same process again, removing a bit more material. If the door works fine, simply apply clear finish or paint over the area that you worked on and you’re done.
A sticky door is a simple fix that can save you a lot of money. Most contractors will charge a minimum of 1-2 hours for this simple fix that you can do yourself in just a few minutes.
Source : http://www.ctv.ca/