We have tiles through out our house expect for the bedrooms and unfortuantley there really isn't much you can do!

apart from spending most of your time in the bedrooms if they are carpeted and its just something you have to watch. I use to put pillows around my boys when they were first learning to sit up in case the tipped, but it does get harder when they are crawling from spot to spot!

I guess if you were really worried, you could always buy a baby bike helmet and get him to wear that! lol (although the weight of that might make him tip more! lol)