I think that the cost of building a house this way would leave most potential home owners who live there unable to afford it. For it to be effective and not just give you a false sense of security, it will need to have steel doors and no windows. I certainly would not want it as I can't imagine what it would cost to maintain a house like this. Furthermore, the ground moves quite a lot here in North Texas so foundation problems are very common, so a house has to flex a little with these movements. If it's made from concrete, I expect that you will see cracks in the walls pretty quickly, which will be very expensive to repair.
I guess that the point that I'm trying to make is that you can spend a pile of money mitigating the risk of being hit by a Tornado by building an ugly fortress that no one can afford to buy or maintain, and then never get hit by a Tornado. The smarter thing to do would be to build a safe room within the house (usually a bathroom or a room under the stairs). This has proven to save lives, costs considerably less and does not change the aesthetics of the house or your quality of life.
Many homes in Tornado prone areas already have this, but depending on the price, or location of the house,it may not.
We also need to remember that in America, if you have a low income, you're still encouraged to buy a house as the government is not going to give you one for free. So there's a market for low cost housing that allows people with low incomes to get on the property ladder....as there should be.
I'm not sure about the Bangladesh part, for me that would be a good example of how a concrete building can give you a false sense of security.
http://www.nytimes.com/2013/05/23/world ... .html?_r=0
