Prefabricated home design, which has a 100-year history, is one of the most efficient ways to build homes. (Though in recent decades, some prefab styles have been associated with cheap materials and shoddy construction.)

Factory workers build its parts off-site, then they are then shipped and assembled — a process that usually takes anywhere from 10 to 50 weeks.

Avava Systems, a startup based in San Francisco, has designed prefab tiny homes, called Britespaces, that can go up even faster. CEO Benjamin Kimmich tells Business Insider that Britespace construction takes four to six weeks. This is incredibly fast; many other prefab startups promise 10-week builds.

Avava ships a house's parts in flat-packed boxes (à la Ikea), which speeds up the time and efficiency of getting from the factory to the site, Kimmich says.

The startup works with third-party construction crews to build the actual homes.

In spring 2016, Avava launched three different-sized models, with base prices that range from $117,000 (shown in the rendering above) to $223,000. The price includes permit fees, construction, and contractor services, but owners need to buy their own furniture and appliances.

The homes are available to order in the US through Avava's site. Take a look at the designs: