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  1. Zoning
  2. Ontario, CA
  3. HDR-45

Ontario, CA · zoning record

HDR-45 zoning in Ontario.

The dimensional standards that govern what you can build in the HDR-45 district, straight from Ontario's ordinance, with every figure quoting its source. Check a specific address to see how these rules apply to a real lot.

Free · Every figure cited · Read from the current code (2026-10-02)

HDR-45 dimensional standards.

These are the letter-of-the-law limits for the base HDR-45 district. Overlays (historic, neighborhood plan, and similar) can tighten them; a specific address check resolves the overlays that actually apply.

Maximum building coverage

70 %

Share of the lot the building footprint may cover. This is the rule for a detached house; the code sets other values below.

“4. Maximum Lot Coverage 55% 60% 70%”Table 6.01-2A: Small Lot Traditional Single-Family Residential Development Standards › to maximum, in dwelling units per acre) › 4. Maximum Lot Coverage › HDR-45 column · Ontario code · read 2026-10-02
Other values, by what you build · 1
  • Table 6.01-2B: Small Lot Alley-Loaded Single-Family Development Standards70 %
    “5. Maximum Lot Coverage 55% 60% 70%”Table 6.01-2B: Small Lot Alley-Loaded Single-Family Development Standards › Dimensions › 5. Maximum Lot Coverage › HDR-45 column · Ontario code

Sources

Every figure above is quoted verbatim from the current ordinance. We never substitute a typical-for-zone default: a field absent from the record shows nothing, not a guess.

Informational only — not a permit, appraisal, or professional engineering opinion. Verify with your local planning department before acting on it. See Terms and data sources.

Other Ontario districts on record.

MDR-11MDR-18LDR-5MDR-25

Check a real Ontario lot against HDR-45.

See how these standards resolve on a specific parcel, with the overlays that actually apply, in about 20 seconds.

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