That's only for those folks stupid enough to try and "CLEAR" their home when they hear that bump in the night. Stay put in the master bedroom, stay out of the line of fire with the bedroom door. Call 911 and wait for the cavalry. If you have kids in the home, get them into the safe room immediately! That is the ONLY reason to leave a covered position! Tell the 911 Operator the address first thing, then tell them your position in the home. Instruct the operator to send the cops to your bedroom window and you will toss them your house keys with permission to enter. Tell the operator and cops you're armed. When a cop knocks on the door and slides his ID under the door for proof, THEN and ONLY THEN exit the safe room leaving the gun behind and having your hands in plain sight. Don't be surprised when you see the drawn guns aimed your way. Cops have to be careful, too.
And, as more than one expert has pointed out, for close quarters the only man-portable weapon more effective than a shotgun is a flamethrower.