Oakland and Berkeley Hills
Fog-influenced with mild temperatures. Many homes lack AC and function fine without it. Focus on efficient heating systems.
Flatland Cities: Oakland, Berkeley, Alameda
Warmer than hills but moderated by bay proximity. AC is nice but not essential. Heat pumps work well here.
Central East Bay: Hayward to Fremont
Transition zone between bay influence and inland heat. Balanced heating and cooling needs. Good candidates for efficient dual systems.
Tri-Valley: Dublin, Pleasanton, Livermore
Hot summers regularly exceeding 100°F. Robust cooling capacity is essential. High-SEER equipment saves significant money.
Contra Costa Inland: Walnut Creek to Antioch
Similar to Tri-Valley—hot summers, moderate winters. Strong cooling needs. Consider shade trees and insulation for long-term comfort.
Sizing Considerations
Inland valleys need 20-30% more cooling capacity than coastal areas. Oversizing for coast homes is as problematic as undersizing for inland.