This private residence, currently under construction, occupies a striking site within the Alladale Wilderness Reserve in the Scottish Highlands. With expansive views and a strong connection to the surrounding landscape, the building complements the estate’s wider regenerative ethos. Cayford was appointed as mentor and energy consultant to support the design team, led by Savills Architecture, in targeting full Passivhaus certification. Through an iterative design process, we developed an energy model using SketchUp and DesignPH, importing into PHPP to test and refine performance. This approach provided valuable insights, allowing the design to optimise solar gain in response to the site's cold climate and extensive glazing - an important client requirement. The result is a high-performing building that balances comfort, environmental responsibility, and architectural ambition.