Just Google “prefab in Seattle” and you will get a near-endless supply of startup companies trying to get their pre-made kits in front of what appears to be a growing movement, especially in Seattle and the rest of the Pacific Northwest. Some companies have established their identity and others are looking for footing. They all want in on a new wave.

But what is prefab good for? That list is pretty long too, if you ask the proponents of the style

For residential, it can be cool, sustainable, less expensive (or more expensive, depending on how you do it), architecturally intriguing and hip. For businesses, all the above still fit, but so does the idea of not shutting down while creating your new pad.

A key draw to prefab within cities really is the ability to crane in a new structure, sometimes in as little as a day, depending on the size of the new place.

A recent Greenfab demonstration home in December (a company working to promote the prefab movement) went up in less than six hours. Aiming for Seattle’s first LEED Platinum modular residence, the prefab movement wants to hit a new level of quality sustainable respectability.

This particular home, which really serves as an example of what is out there—although, admittedly, the variations are as extreme as you can imagine—is comprised of six prefabricated boxes made in Boise and dropped, by crane, onto the Seattle site. The new resident, a co-owner of HyBrid Architecture | Assembly, who also served as the project’s architect and general contractor (HyBrid is one of the many Seattle-based firms specializing in a variety of versions of prefab work), offered up his previously undeveloped portion of a subdivided property for the demonstration (yeah, the publicity was a nice incentive, right?).

While a great demonstration, the idea also shows where prefab is taking off the most: in cities with densely populated areas and existing structures all around. With backyard cottages now allowed—an entirely different sub-niche in prefabrication—and vacant lots available, prefab is quickly becoming the way of choice for urban infill, largely because you can simply drop in the home into a tight urban footprint.

Getting these homes ready fast (70 percent of this particular home was completed before it arrived on site and the rest of the work will finish in February, about two months from the drop-in point) also cuts waste, which can be up to 70 percent versus a traditional build.

As more and more companies get in the prefab game and each with their own niches, it remains interesting to watch how prefab has turned from niche market to mainstream. And as more sub-niches develop, it will remain interesting to see where prefab takes us next.