Some tiny properties appear so ideally suited that it’s tempting to keep away from altering them, even when life calls for in any other case. That’s how Pam Austin felt when her household started 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 purchased the little home, which sits on a beachfront lot, as a getaway from their main residence in Seattle. On the time, Ms. Austin, 72, mentioned, “it was charming, however in dangerous form” — overrun by mice and riddled with mildew.

The construction had been constructed on one other island within the early twentieth century, neighbors instructed her, and within the Nineteen Forties it was dismantled, floated and reassembled at its current web site. Greater than half a century later, it was in such disrepair that “the individuals who owned it earlier than us wouldn’t even keep within the cabin,” Ms. Austin mentioned. “They’d simply pitch their tents in entrance.”

Within the years that adopted, she introduced the one-room cabin again from the brink with assist from household and mates. They cleaned it up, evicted the mice and repaired the chinking between the logs. Simplicity was the tenet. The one-room cabin has a small, bare-bones kitchen, a stone hearth, a wood-burning range and a built-in nook with a mattress for sleeping — and that appeared like sufficient.

“It’s only a very easy place the place the youngsters might run in with sandy ft,” Ms. Austin mentioned. “There’s nothing valuable.”

As time went on, nevertheless, she met a brand new companion who shared her love of the cabin, William Pence, 73. Her sons, Eric David, now 30, and Alex David, 28, grew up and developed relationships of their very own, and Ms. Austin suspected there may quickly be grandchildren.

Asking her sons to pile into the tiny cabin once they visited now not appeared possible. “They’re adults now and don’t need to sleep with Mother, on a cot,” Ms. Austin mentioned. But she nonetheless wished the property to function a household compound.

Many in her place might need thought-about constructing an enormous addition or demolishing the previous cabin to exchange it with one thing new. However Ms. Austin wasn’t ready to let the cabin go or have it swallowed up by an extension. It was her comfortable place, and it held too many reminiscences.

“I wished the footprint to be as small as attainable,” Ms. Austin mentioned. So she determined to construct a compact bunkhouse behind the unique cabin and requested the Seattle agency Shed Structure & Design for assist.

She instructed Prentis Hale, a principal at Shed, that she didn’t need the bunkhouse to have a full kitchen and lounge. She wished it to offer sleeping house solely. That method, she mentioned, “all of us have to return collectively right here on the cabin — that is the place the place we collect.”

Mr. Hale beloved the concept. “Today, all people builds a a lot bigger home proper on the water — these gargantuan initiatives that don’t have lots of contextual siting,” he mentioned. “I agreed together with her choice, as a result of it’s simply not possible to recreate a hundred-year-old cabin.”

After finding out the positioning, the architects designed a two-story, 590-square-foot bunkhouse threaded between mature fir and cedar bushes behind the unique cabin. The bottom ground comprises a mudroom, rest room and small kitchenette. The upstairs has three sleeping areas separated by wooden slats and curtains. On the prime of the steps, there’s built-in seating beneath an expansive skylight, with cushions that double as twin mattresses. On both facet is a bed room with a queen-size mattress and a pair of bunks.

Responding to Ms. Austin’s request for easy, sturdy supplies, the architects used plywood for the built-in furnishings and to line the inside partitions. On the flooring, there’s extra plywood and eco-friendly Marmoleum flooring. Low-cost porcelain lamp holders function sconces, and the toilet is fitted with drop-in stainless-steel sinks. Jennie Gruss, an inside designer, helped Ms. Austin usher in coloration with patterned throw pillows and striped bedding.

Outdoors, the decrease degree of the bunkhouse is clad in dark-stained log-cabin-style siding to match the unique cabin. The place the highest degree extends cantilevers out to create a coated porch, it’s supported by a pair of tree trunks that Ms. Austin’s builder, Kaplan Properties, discovered washed up on the seashore.

Ms. Austin and Mr. Hale used the development venture as a possibility to put in a brand new septic system and to unravel one other downside: The previous properly had run dry. To supply water for each buildings, Mr. Hale designed the roof of the bunkhouse with gutters that acquire rainwater, which is pumped into cisterns and filtered to be used.

Development took a couple of yr and was accomplished final December, at a value of about $600,000.

It gave the impression to be simply in time, as Ms. Austin’s household continues to broaden. Along with spending extra time on the property in the course of the pandemic, her son Eric had his wedding ceremony there in 2021.

“I’m going to be a grandmother in April,” she mentioned. And the compound, she added, is already functioning as she hoped it could.

“We had Christmas right here, we had Thanksgiving right here, and we had my birthday celebration right here,” she mentioned. “All people comes — so sure, it’s working.”

Residing Small is a biweekly column exploring what it takes to guide an easier, extra sustainable or extra compact life.

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