This 1,300-square-foot auxiliary residence on Lake Tahoe’s North Shore integrates modern design, careful planning, and environmental sensitivity within a rugged mountain setting. Nestled on steep terrain with over 75 feet of descent, the project required innovative architectural and engineering solutions to create a versatile retreat that serves as a gym, guest quarters, and outdoor entertaining space. The design replaced a dated and failing home with a new building that blends form, function, and sustainability. Steel framing and cross-laminated timber (CLT) panels provided durability, fire resistance, and thermal efficiency, while allowing for a simple single shed roof. Nearly 40-foot-long CLT panels were lifted into place by crane, showcasing precision and efficiency in construction. Expansive sliding doors open to an 800-square-foot deck, blurring the boundary between indoors and out. The program consists of a gym/recreation room, an indoor/outdoor kitchen, a single bedroom with en-suite bath and second bath with a sauna - all oriented toward maximizing lake views and promoting health and wellness. The steep site, defined by boulders and mature trees, required intensive landscaping with hand-placed natural materials. Walkways connect the residence to the surrounding property and lead to the lakefront pier, preserving the rugged character of the landscape. Sustainability measures were integral. A VRF heat pump system eliminates natural gas use, roof-mounted solar panels provide renewable energy, and permeable hardscape materials support storm water infiltration. Durable, energy-efficient materials and careful detailing ensure longevity while minimizing ecological impact. The result is a modern, resilient mountain retreat—functional, sustainable, and deeply connected to its natural setting.