[AngryData]

You still can build a house that way, building to code is not hard, it only becomes any sort of problem once you start doing crazy shit like open spans 20 foot wide or vaulted ceilings, and even then, there are simple standards for most of that too, which is why the building codes are so extensive. With a couple months of work or training anybody could build a house to code by themselves without a problem. The only real consideration for not doing it yourself is your speed. Some guy that frames all day every day is going to get that job done multiple times faster from practice and have more than all the tools for anything they will encounter, but if you have the time and can swing a hammer then you can do it.