What’s Better Than a Tiny Island Cabin? Two, Side by Side.

Some tiny homes seem so ideal that it’s tempting to avoid changing them, even when life demands otherwise. That’s how Pam Austin felt when her family began outgrowing the 450-square-foot log cabin she owns on Guemes Island, off the coast of Washington.

In 2000, Ms. Austin and her now ex-husband bought the little house, which sits on a beachfront lot, as a getaway from their primary home in Seattle. At the time, Ms. Austin, 72, said, “it was charming, but in bad shape” — overrun by mice and riddled with mildew.

The structure had been built on another island in the early 20th century, neighbors told her, and in the 1940s it was dismantled, floated and reassembled at its present site. More than half a century later, it was in such disrepair that “the people who owned it before us wouldn’t even stay in the cabin,” Ms. Austin said. “They’d just pitch their tents in front.”