This project involved the development of a brand-new, detached Accessory Dwelling Unit (ADU) designed to meet rigorous California energy standards. The architectural design features a modern ranch-style aesthetic with a focus on sustainable building envelopes, incorporating specialized materials such as Hardie trim and high-efficiency exterior plaster. The structural design includes a slab-on-grade foundation and a complex roof system with a 13′-9″ ridge height to maximize interior volume while maintaining a compact footprint.

To ensure full compliance with California’s Title 24 Energy Code, the project utilized advanced “Cool Roof” technology featuring Timberline HDZ RS shingles in Sandalwood. This specific roofing material provides an initial solar reflectance of 0.21 and an aged Solar Reflectance Index (SRI) of 19, significantly reducing heat absorption and cooling loads for the dwelling. The thermal envelope was further enhanced with high-performance insulation, including R-21 insulation for exterior walls and R-38 insulation within the attic spaces.

The engineering focus for this Title 24 report centered on balancing the large window-to-wall ratio with high-efficiency glazing and mechanical venting. By integrating specific energy-efficient components—such as 18″ dormer vents with a net free area of 5.55 sq. ft. and moisture-managed wall assemblies—the project achieves a high level of sustainability. This comprehensive approach ensures that the new residence provides a comfortable living environment while minimizing its long-term carbon footprint and energy costs.