The people moved out of the house at the end of March and set the temperature down to 55-60 and then we moved in a week later and put the temperature back on normal.
After moving everything was good for a few weeks. Sometime in the beginning of April (less than a month) I noticed that the door to the upstairs bedroom no longer latched close unless you pulled up on the door, a few weeks later even pulling up on the door didn't help, it closes fine but doesn't latch and I notice the gap along the top of the door is wider on one side than the other.
Towards the end of April I started noticing cracks in the drywall appearing. Most of the cracks started in the upstairs. The master bedroom has two hairline cracks (both going directly up to the ceiling), one above the door that won't latch and another on the opposite wall right above the window. The upstairs bathroom has a crack in the corner wall. The upstairs office has a crack above the window going directly up to the ceiling and the door in this room has a diagonal crack going from the corner of the door frame.
Downstairs there are three places where I have a crack going from a door/window frame directly up to the ceiling and finally there is a crack in the downstairs bathroom between the wall and ceiling.
How much drywall cracking is normal? I am not sure if I should be worried about this or not. Since I have only been living here for a few months I thought that I might wait till the fall and see what happens, I read online from one person that seasonal changes can cause cracks to appear and then disappear. I am not sure if thats a good approach or not. I also did make a call to a contractor but after talking with him I guess I got scared that he didn't seem knowledgable enough, so I want to find out as much as I can beforehand so I can be more intelligent about this.
Now for a little bit more info that I am not sure matters. The washer is on the 1st floor and the people who moved out had a top-loader, I brought in a front loader. I notice that when I am up in my office upstairs and the washer spins, I can feel a slight vibration. The washer itself doesn't seem to too vibrate much but the way the house is built you can feel the slight vibration. I am not sure if this could be causing the cracking in the drywall?
My wife is always cold too, so I don't use the A/C too much, probably much less than the old owners. So could the humidity change in the house be causing this?