It looks like it's about to collapse any minute now under it's own weight, since there's no support for the upper floor part on the right. The textures are a tad too much the same and the house has some weird unused space on the "roof". Overall there are indeed some spots that need some work. It's cool to design more abstract houses, but it wasn't instantly obvious to me at all that this was a house, that's a bad thing. (it looks more like a factory, but with an odd scale)

Btw I'd be interested to see this demo, can't you upload it to one of those uuhm upload sites??

Cheers