Free Tool
San Diego County, California
Calculate your buildable area based on San Diego's zoning requirements. Enter your lot width, depth, and zone code — get an instant visual diagram showing exactly where you can build. San Diego residential zones typically require a 15' front setback, 5' side setback, and 13' rear setback, but this varies by zone.
Provide your lot width and depth in feet. You can find these on your property survey, title report, or county assessor records.
Choose from 10 major California cities. If you know your zone code (R1, R2, etc.), enter it for precise setback values from your city's municipal code.
Get an instant visual showing your buildable envelope — the area remaining after setbacks. See max footprint, coverage percentage, and height limits.
Building setbacks are the minimum distances your structure must be from each property line. Every California city defines setbacks by zone — residential zones like R1 typically require larger setbacks than commercial zones.
There are three types of setbacks:
Setbacks affect your buildable envelope — the area of your lot where construction is physically allowed. Understanding your setbacks before you design saves time, avoids plan check rejections, and prevents costly redesigns.
While setbacks vary by zone, here are typical residential setback ranges across major California cities:
These are starting points — your specific zone may differ. Always verify with your city's municipal code or run a full plan check before submitting plans.
Check your property survey (from when you purchased), title report, or your county assessor's website. You can also measure using Google Earth or search your address on LotCheck's parcel search to see lot area. For exact dimensions, a licensed surveyor can provide a certified lot survey.
Building within a setback without a variance is a code violation. Your city can require you to demolish the encroachment, deny a certificate of occupancy, or issue fines. Some cities allow setback exceptions through a variance process (typically $5,000–$15,000 in fees and several months of hearings).
Yes. Under California state law (AB 68/AB 881), detached ADUs only require 4-foot rear and side setbacks, regardless of what your city's zoning code says. Front setbacks still apply. This makes ADUs viable on lots where a standard addition wouldn't fit. Check your eligibility with our ADU Eligibility Checker.
Yes. Many California cities increase side setback requirements for two-story construction — often by 1–3 additional feet. Some cities also have "transitional height" rules that increase setbacks when your building is significantly taller than neighbors. This calculator uses standard single-story setbacks as a baseline.
Setbacks define the minimum distance from property lines. Your buildable area (or buildable envelope) is what's left after subtracting all setbacks — it's the rectangle where your building footprint can go. Note that your actual building may be smaller than the buildable area if lot coverage limits apply. Use our FAR Calculator to check floor area limits.