Factory-produce modular housing units that fit inside a 40&#x27; high cube shipping container.  Factory-produce the 88&quot;L x 40&quot;W X 30&quot;H modules and the 4&quot;L x 80&quot;W x 90&quot;H bulkheads that separate them.  Each unit would have four internal bulkheads and up to 18 room modules that aren&#x27;t a 40&quot; wide pass-through space.  Each &quot;room&quot; would consist of three or six stacked modules, and each module is small enough to fit through the doors when disassembled.  Side doors can be opened on each side of rooms 2 and 4.<p>On-site construction consists of a concrete foundation pad, steel racks, and an outer weather shell appropriate for the region.  Utility hookups are provided for each berth.<p>When a new housing unit is needed, it arrives in an intermodal shipping container, rolls into an open berth in the rack, is anchored in place, and the utilities are connected.  If anyone needs more space, the internal doors and modules can be reconfigured to join multiple units internally.<p>Current manufactured housing in the US is premised upon hauling the pieces to the site by truck.  If housing could also be moved by container ship and stacktrain, it is more easily importable and exportable.<p>A size standard for home modules opens up a huge aftermarket.  Don&#x27;t like the factory-installed kitchenette or don&#x27;t cook?  Swap it out for an exercise room or workbench or hydroponics garden or nursery or whatever else you may want in its place.  It fits.  The utility connectors are in the same place.<p>The number of berths in a rack and the size of the outer weather shell can be different for different housing markets.  One near a city might have multiple levels, cramming dozens of units into a single shell with a fashionable brick facade.  One far out in the country could have space for as little as just one unit--and it might not even be filled all the time--but it might also have a tornado-resistant outer concrete shell.<p>If you change jobs, rather than pack up your possessions, you could just secure all your loose items inside and ship your owned housing units to an empty berth in a new rack, across town or in a different city.<p>The major problem is lack of elbow room.  You just can&#x27;t cram very much living space inside a shipping container, so even if you connect many units, your home still consists of a maze of doors joining a bunch of 48 sq.ft. rooms.