I've got a 36"X24" Bulldog target.I'm building a stand for it outside,but for now I've got it stored in my "Man cave" room. I can stand in our living room and shoot into the other room,about a 10 yard shot.
a couple things I've learned since I've started shooting inside...
1-ALWAYS make sure you know where the dog is before you shoot!(No,I didn't shoot him! He was sleeping behind one of the bookshelves between the rooms. When my arrow hit the target,the "WHACK" scared the bejesus out of him and he came tearing out into the living room,crashed into a tray table with a glass of water on it and spilled it onto a brand new couch! Thank god it was only water.
2-DO NOT let your 8 year old daughter take a shot from the full 10 yards.(look close at the bookshelf to the right of the target and you can just see the mark!)
3- If you want to continue to shoot in the house,don't let your wife find out about 1 and 2.