Your dog is a smart, adaptive creature who can quite readily use his natural intelligence to make living in a human home as comfortable as possible. Provided you don’t have extremely heavy or automatically-locking doors, your dog can easily use his paws to open them. Some dogs may require training to master this trick, others will figure it out themselves in no time. This depends on the personality of your dog and the layout of your home; if there are lots of doors, he’ll most likely figure it out by himself.
A dog typically opens a door by pushing it with his paw. Naturally, this only works if the door is already ajar. If the door is shut, your dog can open it by standing on his hind legs and pulling the handle down with his paw, before either nudging it open with his nose, or pushing it with his paw. If the door opens toward the dog, he’ll most likely nudge it open with his nose.
For a dog to teach himself door-opening skills, there needs to be a reward on the other side. This reward typically comes in the form of contact with humans. Sometimes, the smell of food or the presence of another dog is enough to make him open the door himself. In short, for many dogs opening the door is a self-rewarding action that requires very little training or encouragement.
To train your dog to open doors with his paw, you first need to get him to perform the pushing action with his paw. This is called target training. By rewarding him for raising his paw to your hand on command, you quickly get him in the habit of “pushing,” then all you need to do is change the target from your hand to the door. With doors that have a handle, you’ll need to teach him to stand on his hind legs as well, so he’s in a position to push on the handle.
There are benefits to the training, as well as the actual skill. Target training is a stimulating and challenging exercise. Once your pup's figured out how to open the door, you can send him to the yard to go relieve himself or if you’re feeling really lazy, you can teach him to fetch items from other rooms. Sometimes door-opening skills can save a life. In 2011 a dog living in South Carolina used his door-opening skills to escape the heat of a fire in his home.
If you want to isolate your dog for a period of time, for example as correction for bad behavior or because you need him out of the way, you may find that his door-opening skills present a problem. If you’ve training him correctly, he should only open doors on command, but dogs can be persistent and hate being alone, so do keep this in mind if you plan on training him to open doors with the handle.