I actually looked up some stuff, and my personal conclusion is (because I'm still not 100% sure) that before it was nazi-related, the swastika was always portraited like a cube, resting on 1 side. The nazi-symbol always balanced on a corner. This particular swastika is also balancing on a single corner, so I think it actually is nazi-related. I immediately lay a link with the KKK, but I thought they were situated in the more southern states (?) Fact is that it is pretty weird for house decoration. (Also found that native americans use this as well (for peace and good luck), so that could be another thing which is not nazi-related)