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Green's Floating Cottage

Type: Stand-alone cottage
Footprint: 433 square feet
Location: Portland, Oregon
Created: 2008

This floating habitation is a guesthouse for another houseboat, which owners Charlotte and Michael Green built before the main house to test the idea of living on water. Boat slips in this marina were much cheaper than building lots, and the location couldn't be better, situated near a nature preserve and minutes from downtown Portland.

When it comes to the typically smaller footprints of in-law spaces, clever design can make all the difference. The Greens hired architect Russ Hamlet, a small homes specialist, who employed tricks such as choosing stairs without risers to the sleeping loft to help the limited space feel more open. The house's corrugated steel roof reflects light from privacy-protecting high windows, and green glass tiles in the shower serve the same function.

Photo: Art Grice | "In-Laws, Outlaws, and Granny Flats" published by The Taunton Press in 2011