I'm currently helping a friend build a house in Austria, where houses are generally brick and concrete. You don't want to build the walls out of concrete. Use t

I'm currently helping a friend build a house in Austria, where houses are generally brick and concrete. You don't want to build the walls out of concrete. Use thick thermal bricks, he kind with lots of internal cavities. Then, if you are in a really cold climate, apply a layer of thick rigid insulation on the outside, followed by a rigid top coat. Floors and ceilings only should be poured concrete.