Our homes are filled with doorways. They go in between rooms, into closets and to the outside world. You might not pay much attention to them as you step through, but there is a big difference between a door that is properly installed, and one that is not.Installing a door is not a simple task, and if it is done improperly, it might not just be an inconvenience to open and close the door, it could actually cost you money in the future.A poorly installed door could do damage to the doorway itself, warping or misaligning it. It could also void the manufacturer’s warranty.A well installed door depends much on the frame it is situated in. Before putting a new door in, you want to make sure that the door frame is square, plumb, firmly attached and properly aligned. If any of those things aren’t true, your door might look good when you install it, but it will certainly not stay that way.