A new architect needs to know first: is it supposed to be a real house scaled or something what looks like a house. The trouble is, the real house scaled, looks sort of flat... The plucky link tells you for example to use 1/4 inch for 1 foot (very difficult to work with, trust me). A real floor of such house would be only 2 inches tall (8 feet scaled). The modellers most of the time distort proportions...
Now, the foam board (somewhat expensive but excellent material) is usually 1/4 inch thick what does great job as a wall in 1/2-inch scale and would look massive in 1/4-inch scale.
If it's a real, residential house "architectural" mock-up, I would recommend using 1/2"=1' scale: you'll be able to actually put your hands inside. A real dimensions of say 30'x40' will scale to 15"x20", while say 2 floors and the roof might be about 30' tall, in this scale it's about 15". Over all, you'll end up with a model about the size of a monitor.
Few things to remember what miniature creators seem always to forget.
- Except for garage, floors are not on the level with the ground.
- Think about presentation: do you need to show inner wall arrangement or it is not important?
- Finishing: you could simply print a window on paper and glue it on the wall or go for the works...
I'd also avoid designing a house. Can you make a model of an existing one? Have fun!