Passive Tiny House Design

Here's the latest layout for our tiny house.  I'm proposing an independent study at MIT in which I'll work on the designing the house's off-the-grid energy systems and doing structural calculations.  It's definitely feasible to just build the house without doing all the calculations, but as we're trying to build as cheaply as possible, it's important to know where to skimp and where to invest.  We will try to get a lot of materials used or donated and it would be nice to be able to calculate the long-term value of a 20 year old free window compared to paying money for a new window that might help keep warm air in better in the winter and last longer.  It's a delicate balance between dollars, inches, and years.