Retrofitting

Houses can be retrofitted to be more like an earthship, but obviously it is limited by the design of the original building and location.

Ideally the house is:
 * Facing the equator
 * Is long East-West.
 * Has room to pile dirt around the outside.
 * Has room for a greenhouse on the equator side.

Adding systems
Typically can reduce sewage to zero and reduce electrical intake to zero.
 * Add greenhouse to equator side, wrapped around the building. This is important for any locaiton that has a winter.
 * Add mass where possible, e.g back wall of greenhouse and around outside of building.
 * Add plant beds in greenhouse.
 * Address the roofing, e.g. by making safe surface to collect water off.

Philiosophy
Important to remember that unlikely can turn a house into an earthship, so instead goal is to make the house perform better.

Also, since it is expensive, suggested to just retrofit the 1~2 rooms that use the most.

When approaching a retrofit, good idea to appoach the building as terrain, so do what ever you can to make the "terrain" to work for you. One way to approach retrofitting as making a series of "nests" in the building,

When a building has been made so tightly insulated and protected, a tiny amount of heat can be sufficient. A couple of people

Importance of retrofitting in the bigger picture
Considering the vast majority of people already live and own conventional houses, retrofitting is very important part of changing people's living habits around the world.