I am hoping this could be the right forum for this kind of question. I recently bought a house that is going to have major structural changes and an extension that will basically be new-build. I am pretty much a novice to all this.

I am thinking about the electrics, naively, and wondering what kind of cost savings and simplifications could be achieved by trying to run DC around the house.

My thinking is that 

* I want efficient (LED?) lighting (DC)
* If necessary, perhaps I could pipe the light by cheap fiber optic, if that ends up being part of the solution
* Most things I use around the house either run off DC or will be rechargeable via USB anyway.
* I will still need a few AC sockets for things like the hoover, but not many

I am aware that low voltage DC will suffer voltage drop and power loss, and that fat cabling to compensate would make that more expensive, but what I am thinking is that because this is so early in the construction, are there any opportunities for taking advantage of decorative or structural elements as electrical conductors?

* Can I use steel reinforcements, even in steel-concrete, as the DC distribution network?
* Other structural and/or decorative elements such as aluminium bars, copper plates and etc., that when arranged could also serve as DC distribution

In short, in our current home it seems absurd at face value that we have all these little USB adapters and chargers lying around, transformers, wall-warts, bricks and etc., when it seems all I really need is a USB socket in a wall. I am wondering if there is any realistic way of achieving this that makes general sense.