Journal ·
Pasadena Neighborhood Compatibility: The 500-Foot Median Rule
On a single-family lot in Pasadena, the size of the house you can build without a discretionary permit is set by the neighbors, not only by the lot. Section 17.22.040 of the Pasadena Zoning Code limits a house in the RS and RM-12 districts to 35 percent above the median house size of all properties within a 500-foot radius. Going past that line takes a Single-Family Compatibility Permit, and even then the house stays under a second cap tied to lot area. On one RS-6 lot on East Rio Grande Street, city staff put the neighborhood median at 1,196 square feet, which made 1,615 square feet the most the house could reach without the permit, on a lot whose own cap was 2,966.
What is Pasadena's neighborhood compatibility rule?
The rule compares a proposed house with the houses around it. City staff restate it in each case report: under Zoning Code Section 17.22.040, "the allowable floor area of a house shall not exceed 35 percent above the median house size of all properties within a 500-foot radius of the subject property," and that radius "shall serve as the project's 'neighborhood' for purposes of neighborhood compatibility."
Two limits therefore apply to the same lot:
- the compatibility ceiling, which is the 500-foot median plus 35 percent and counts the house only
- the maximum gross floor area for the lot, which counts all structures on the site
In general, a design under the first number needs no compatibility permit, a design between the two needs one, and the permit does not lift the second number. ADUs are treated separately, as explained below.
This article covers single-family lots outside the overlays. Lots in a landmark district, the neighborhood overlay or the HD Hillside Development overlay can follow different standards, so confirm the parcel's zone string first. Hillside lots are governed by separate hillside rules, covered in our Pasadena hillside guide.
How does the city calculate the 500-foot median?
The city's submittal checklist for the permit (revision dated January 3, 2022) spells out the method. The comparison uses the "MEDIAN dwelling size (middle dwelling size, not the average dwelling size)," and the sizes come from Los Angeles County Assessor data for the primary residence. The checklist tells applicants to list the developed single-family lots in the radius, the subject lot included, rank them from largest to smallest and take the middle value. With an even count, that is the average of the two middle houses.
What the Assessor number leaves out matters. In the October 2025 report on case SCP #7222, staff note that the Assessor data "only includes the square footages for the house; the data does not include basements, attics, attached garages, accessory dwelling units, and any detached structures." So the median leaves garages and ADUs out, and the proposed house is compared with it as a house-only figure, without the garage.
In practice the list can reach past single-family streets. In that same case, staff's list of 141 developed properties includes parcels zoned RM-32 on East Washington Boulevard, three of them with Assessor house sizes over 12,000 square feet. The median still landed at 1,196 square feet, because a few very large buildings barely move a middle value.
Owners can pull the figures from the Assessor's property portal, or request a compatibility analysis from city staff by letter, for a fee.
How big can the house be with a compatibility permit?
The permit lifts the compatibility ceiling but keeps the lot-area cap. Staff reports apply that cap as a formula on lot size. On the RS-6 lot of 8,220 square feet it was 30 percent of lot area plus 500 square feet. On the RS-4 lot of about 13,500 square feet it was 20 percent of lot area plus 1,700 square feet. The table in Section 17.22.040 switches between those two rows at 12,000 square feet. Lots of 24,000 square feet or more and RM-12 lots follow other rows, so they are left out here.
Applied to other RS lot sizes in the same range, those two formulas give these caps for all structures on the site, garages included. Treat them as estimates until Planning confirms the row for a specific parcel.
| Lot area | Formula staff applied | Maximum gross floor area |
|---|---|---|
| 6,000 sq ft | 30% of lot + 500 | 2,300 sq ft |
| 7,500 sq ft | 30% of lot + 500 | 2,750 sq ft |
| 10,000 sq ft | 30% of lot + 500 | 3,500 sq ft |
| 12,000 sq ft | 20% of lot + 1,700 | 4,100 sq ft |
| 15,000 sq ft | 20% of lot + 1,700 | 4,700 sq ft |
| 20,000 sq ft | 20% of lot + 1,700 | 5,700 sq ft |
Setbacks, the encroachment plane, height and site coverage are checked separately and can stop a design first.
What did city staff recommend on recent cases?
Two cases from late 2025 and early 2026 show how far apart the numbers can sit. The figures below come from the city's staff reports, which carry staff recommendations rather than final decisions.
| SCP #7222, E. Rio Grande St | SCP #7340, Linda Vista Ave | |
|---|---|---|
| Zone and report date | RS-6, October 15, 2025 | RS-4, January 21, 2026 |
| Properties in the 500-foot radius | 144, of which 141 developed | 94, all developed |
| Neighborhood median (house only) | 1,196 sq ft | 2,149 sq ft |
| Ceiling without the permit | 1,615 sq ft | 2,900 sq ft |
| Lot-area cap (all structures) | 2,966 sq ft | 4,400 sq ft |
| Proposed house | 2,243 sq ft | 3,980 sq ft |
| Over the ceiling by | 628 sq ft | 1,080 sq ft |
On Rio Grande Street the applicant for a 1,018 square foot bungalow proposed a 450 square foot first-floor addition and a new 775 square foot second story. Taking the house past 1,615 square feet put it into the permit process, even though the lot formula allowed far more. On Linda Vista Avenue, the January 2026 report counted the new 3,980 square foot house plus a 420 square foot garage against the lot cap, matching staff's 4,400 square foot limit. In both reports staff recommended approval with conditions.
What does the compatibility permit process involve?
The permit is not a counter approval. The October 2025 report describes the sequence for upper-story additions, and the checklist asks for the same notification packet for a new two-story house:
- Story poles outlining the new structure are installed on the lot.
- Once the application is complete and the poles are up, a Notice of Application goes to all properties within 500 feet, with a minimum 14-day notice period.
- With no hearing request, the Zoning Administrator may decide, and that decision is appealable to the Board of Zoning Appeals.
- With a hearing request, the Hearing Officer decides after a public hearing.
In both cases above, a request for a hearing was received during the notice period, so the Hearing Officer took the case. The Rio Grande notice ran from May 7 to May 21, 2025. The hearing came in October.
Approval needs two findings, which the checklist repeats. The design, location and size must be compatible with development along both sides of the blockface "in terms of aesthetics, height, materials, massing and scale." The project must also include front setbacks and entryways consistent in scale with the blockface.
Does an ADU count against Pasadena's house size limits?
In the Linda Vista case, staff did not count the attached accessory dwelling unit toward the floor area standards, citing Government Code section 65852.2, a state ADU section since moved to a new chapter. The Assessor-based median also leaves ADUs out of the neighbors' sizes. The current state rule sets a minimum, not a blanket exemption: Government Code section 66321(b)(3) bars local limits on lot coverage, floor area ratio, open space, front setbacks and minimum lot size that would not permit an ADU of at least 800 square feet of interior livable space with four-foot side and rear setbacks.
Fee and covenant questions are in our guide to ADU fee waivers and housing agreements.
What should a buyer check before counting on an addition?
"Room to expand" in a listing says nothing about the median. This checklist turns it into two numbers:
- [ ] Zone string for the parcel, including any HD, landmark or other overlay suffix
- [ ] Lot area from the Assessor, since the lot-area cap scales with it
- [ ] Living area of the house as the Assessor records it, without garage or ADU
- [ ] Median of the developed properties within 500 feet, from Assessor data or a staff letter
- [ ] The median plus 35 percent, compared with the size you have in mind
- [ ] Permit history for any second story or large addition already built
For a seller, a lot whose house sits well under the compatibility ceiling has room a buyer can measure, and a home valuation that starts from these two numbers is easier to defend. Buyers comparing lots can run the same steps while searching for a home, and sellers can see how this fits a listing plan on the selling page. Burbank's rules are in our Burbank floor area guide.
This article summarizes Pasadena Zoning Code provisions as applied in city staff reports dated October 15, 2025 and January 21, 2026. It is general information, not legal or design advice; confirm the limits for a specific parcel with the Pasadena Planning and Community Development Department before buying or designing. Call Alla at (818) 699-5367 or use the enquiry form.
More on the city: the Pasadena area guide.