Rialto R-1 zoning: height, setbacks and lot size

R-1 (Single Family Zones) is a zoning district in Rialto. Every value below was read from the Rialto Municipal Code and links to its section (read October 2026). State laws such as the ADU and SB 9 rules can allow more on a residential lot. General information, not legal advice — read the code text and check with the city before you build.

Development standards in R-1

The general rule for a typical lot in this zone. Zoning tables often attach notes, such as rules for corner lots, lots next to a residential zone, or new subdivisions only. Open “code text” under a value to see the table cell or sentence it was read from.

Maximum building height	35 ft § 18.10.030 · code text Building height limit is two and one-half stories, and not exceeding thirty-five feet.
Minimum front setback	25 ft § 18.10.030 · code text Front yard is twenty-five feet.
Minimum side setback	10% of lot width, min 3 ft, max 5 ft Applies: Interior lots; a side yard is required on each side of the main building. § 18.10.030 · code text On interior lots there shall be a side yard on each side of the main building of not less than ten percent of the width of the lot, but need not exceed five feet nor may it be less than three feet.
Minimum rear setback	20 ft Applies: different rules may apply to accessory buildings § 18.10.030 · code text Twenty feet except as otherwise provided for accessory buildings;
Minimum lot size	8,400 sq ft § 18.10.030 · code text Lot area is eight thousand four hundred square feet.
Maximum lot coverage	30% § 18.10.030 · code text Maximum building coverage is thirty percent of the lot area.

When a different number applies

The code sets other values for particular lots, buildings or locations in R-1:

Minimum front setback: average of the existing deeper front yards — Where lots with 50% or more of the frontage on one side of the block have deeper front yards § 18.10.030
Minimum side setback: 20% of lot width, min 10 ft, max 15 ft — Corner lots; side yard abutting the street. § 18.10.030
Minimum side setback: one-half of required front yard distance — Reversed corner lot; side yard abutting the street. § 18.10.030
Minimum side setback: 2 ft additional per story — Interior side yards for each story above the second. § 18.10.030
Minimum rear setback: average rear yard not less than 20 ft — Corner lots; a portion of the main structure may extend into the rear yard area. § 18.10.030

Not on this page

We did not find a general stories, FAR, density limit for R-1 in the zoning tables we read. The code may still set one elsewhere — check the Rialto Municipal Code.

Other Rialto zoning districts

Who this affects

HomeownersArchitects and designersDevelopersReal estate agents

Frequently asked questions

What is the maximum building height in Rialto's R-1 zone?

35 ft — Rialto Municipal Code § 18.10.030.

What is the minimum front setback in Rialto's R-1 zone?

25 ft — Rialto Municipal Code § 18.10.030.

What is the minimum side setback in Rialto's R-1 zone?

10% of lot width, min 3 ft, max 5 ft (interior lots; a side yard is required on each side of the main building) — Rialto Municipal Code § 18.10.030.

What is the minimum rear setback in Rialto's R-1 zone?

20 ft (different rules may apply to accessory buildings) — Rialto Municipal Code § 18.10.030.

What is the minimum lot size in Rialto's R-1 zone?

8,400 sq ft — Rialto Municipal Code § 18.10.030.

General information, not legal advice.