This is the story of a family that expanded from one generation to several, and of one house that became two. Situated on five acres along the shores of Pleasant Lake, a cozy vacation home first beckoned the owners to retreat from the city to relax near the water and woods. Then, as children became parents and parents became grandparents, the residence was soon outgrown, no longer able to accommodate multiple generations simultaneously.

Kaplan Thompson Architects was hired to design a “low-maintenance, high-delight” guesthouse that would provide more space and privacy for the growing families. Now every level of the new home welcomes inhabitants to step outside via a telescope deck, one of three stacked balconies, or a rope bridge that connects the second story to a nearby raised “play deck.” These elevated outdoor spaces project off the building on dramatically angled timber supports, like a treehouse perched among old maples.

As much as the home is designed to house guests, it will be the permanent residence for a vast collection of books. One family member’s love of storybooks (a passion that runs so deep she is the founder of a nonprofit children’s literacy initiative) inspired many of the project’s whimsical details and necessitated a clever storage solution. Her collection will reach new heights in a bookcase spanning all three stories of the home, accessed by an interior staircase climbing upward around it. Another curved bookcase extends along the entirety of the lower-level gathering room; a tug in just the right spot and a portion of the case swings outward to reveal a hidden entry to the primary bedroom suite.

The guesthouse will be fabricated using Passive House– quality panelized construction. Ecocor, a Searsmont-based construction firm, will manufacture panels to be assembled and finished in a collaborative effort with the project’s general contra tor, Maine Passive House. Thus the structure’s floors and walls will be produced and weatherproofed off-site, then transported to the home site for rapid assembly on the foundation. Each high-performance panel will arrive with doors and triple-glazed windows already installed, and will eventually be clad in weathering copper shingles and durable fiber cement. The completed structure will be powered by a photovoltaic array with battery backup, allowing the whole family to ride out winter storms in comfort.