Castro is located in IECC Climate Zone 4B (Mixed - Dry). Get accurate Manual J load calculations with official design temperatures for Castro.
Climate Zone 4B requires precise load calculations. Upload your Castro blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Castro's exact design temperatures (3°F winter / 92°F summer).
Enter your ZIP code to confirm it's in Castro and get climate zone details.
Official ASHRAE design temperatures for Castro, used for accurate Manual J load calculations.
Minimum insulation and window requirements for Castro per IECC 2021.
Energy Code: 2021 IECC
Upload your Castro blueprint and get a professional Manual J load calculation using official Zone 4B design temperatures. First report is FREE.
Join 10,000+ Castro contractors who trust AutoHVAC