Custom home planning resource · Los Angeles County and the South Bay
Planning a custom home in Altadena
Altadena is an unincorporated community, so Los Angeles County — not a city hall — decides how a new or replacement home is reviewed. After the January 2025 Eaton Fire, the first question for many lots is whether the house will be a like-for-like rebuild or a new design under current County standards.
KB Remodeling takes new-home inquiries from owners planning here. Share the lot and the project; KB reviews scope, licensing and location for each inquiry before suggesting a next step.
Planning sequence
01
Decide: like-for-like rebuild or new design
County Planning defines a like-for-like replacement as the same size, location and land use as the legally established structure, with limited modifications allowed. A larger or different house is a non-like-for-like project.
Official resource: LA County Planning · Eaton FireApplies to a specific area, zone or overlay · Passage checked
02
New designs follow Title 22 and the Altadena CSD
A non-like-for-like project is subject to current development standards in County Title 22, including the Altadena Community Standards District, and County Planning notes a minimum front-yard setback for all non-like-for-like rebuilds.
Official resource: LA County Planning · Eaton FireApplies to a specific area, zone or overlay · Passage checked
03
Know what like-for-like still requires
The County's rebuild FAQ says like-for-like structures need not meet current Zoning Code requirements but must meet current Building, Fire and Health and Safety Codes, and debris removal must be completed before a building permit can be issued.
Official resource: LA County Recovers · Rebuild FAQApplies to a specific area, zone or overlay · Passage checked
Each step links to the official page it comes from. Requirements differ by parcel; confirm with the agency.
Who reviews a new home here
Altadena is an unincorporated community (a Census-designated place) in Los Angeles County. It has no city government; County departments handle planning and permits.
Unincorporated Los Angeles County — Department of Regional Planning (zoning, including the Altadena Community Standards District) with County building and fire review. Altadena has no city government.
Local planning journey
Which planning question to resolve first here, and why it shapes the brief. Each answer comes from the cited City page or stays a question for staff.
Question 1
Like-for-like rebuild, or a new design?
LA County Planning (read October 13, 2026) defines like-for-like as the same size, location and use as the legally established structure; a larger change, such as more than 10% or 200 square feet, follows current Title 22 standards.
source: LA County Planning · Eaton FireQuestion 2
What was legally established before the fire?
Like-for-like depends on the legal prior structure, so permit records matter more than memory.
source: LA County Planning · Eaton FireQuestion 3
Where to start?
The County directs rebuild help to its One-Stop Permit Centers; there is no Altadena city hall or city building department.
source: LA County Recovers · Rebuild FAQ
Finding the current official checklist
Use the County's Eaton Fire planning page and recovery FAQ, then a One-Stop Permit Center, for the current rebuild submittal list.
Owner evidence to gather first
- Permit records or plans for the legally established house
- Pre-fire floor area and footprint
- Debris removal and site clearance status
Altadena rebuild paths under County authority
| Path | Standards described by the County |
|---|---|
| Like-for-like | Same size, location and land use as the legally established structure |
| Non-like-for-like (e.g., >10% or 200 sq ft larger) | Current Title 22 standards, consistent with the West San Gabriel Valley Area Plan |
Source: LA County Planning · Eaton Fire
Local issues and the budget lines they touch
| Local issue | Budget line it affects |
|---|---|
| Choosing a larger design | Design to current standards and longer review |
| Missing records of the prior house | Research or survey to document what existed |
No dollar amounts or local premiums are implied.
Hypothetical: an owner whose house burned wants to add a second story while rebuilding. Because that exceeds like-for-like, they compare the timing of a same-size rebuild now against a larger design under current standards.
Before a 2027 design or build decision here
Local points to confirm with the authority at filing. Broader sequencing lives in the readiness guide. Readiness by stage
- Which County recovery provisions apply when you file?
- Altadena is unincorporated; Los Angeles County is the authority. Confirm with County staff which fire-recovery provisions remain in effect for your parcel at filing.
What shapes the budget here
- Current Building and Fire Code requirements, even on like-for-like rebuilds
- Redesign to Title 22 and Altadena CSD standards if the house grows or changes
- Debris removal, utilities and site preparation before permit issuance
These items affect cost; none is a price. See how to build a realistic budget: Custom home budget guide
Parcel questions to answer first
- Does the plan stay within like-for-like limits, or is it a new design?
- Which Altadena CSD standards apply to a non-like-for-like house on this parcel?
- Is debris removal complete and documented for the lot?
Gather before a first conversation
- Address or APN and recent site photos
- Survey, title report and prior permits if available
- Architect drawings, or a written list of rooms and priorities
- Target timing and how you plan to finance construction
Related guides: Rebuilding after a wildfire · Buying land to build · Lot utility due diligence · Choosing a custom-home builder · 2025 Energy Code for new homes
Official sources
Each source shows what it covers and whether its passage was checked in our review.
- LA County Planning · Eaton Fire
Like-for-like definition; non-like-for-like projects follow Title 22 and the Altadena CSD.
Applies to a specific area, zone or overlay · Passage checked - LA County Recovers · Rebuild FAQ
Codes that still apply; debris removal before permit issuance.
Applies to a specific area, zone or overlay · Passage checked
2 of 2 official source passages checked (latest October 13, 2026).
Page content last updated:
Nearby places worth comparing
- Custom home planning in Pasadena — Pasadena address, but County authority in Altadena
- Custom home planning in La Crescenta-Montrose — Another unincorporated community under the County
Guides that use this place as an example
- Rebuilding after a wildfire — County-led recovery