Carthay ADU Builder: Carthay Circle, Carthay Square and South Carthay

Historic Preservation Overlay Zones and Carthay ADUs

Carthay is made up of Carthay Circle, Carthay Square and South Carthay, and each has its own Historic Preservation Overlay Zone under the City of Los Angeles. An HPOZ does not stop an ADU. What it does is add a preservation review for exterior changes, guided by each zone's preservation plan, on top of the ordinary building permit from LADBS.

That review cares most about what the public sees. A detached ADU tucked behind the main house, out of sight from the street, usually raises fewer questions than a new second story or a change to the front facade. A garage conversion that keeps the garage's original form and swaps the door for compatible windows and an entry tends to be straightforward. The details, though, depend on the specific zone's plan and whether the structure is considered contributing. We review the applicable preservation plan before design and draw the ADU to its guidelines, so the preservation review confirms the design rather than reshaping it.

Spanish Revival Houses and Their Rear Garages

Carthay filled in between the two world wars. Spanish Colonial Revival houses dominate many blocks, with some Tudor, Mediterranean and other period styles mixed in. Carthay Circle took its name from developer J. Harvey McCarthy, and the neighborhood's curving streets and consistent architecture are what the HPOZs protect. Like most homes of that era, many Carthay houses have a detached garage at the rear of the lot, reached by a side driveway. Those garages are the most common ADU site here. In some cases the original garage is a contributing feature and conversion is preferred over demolition. In others, a new detached ADU can replace a later, non-original structure.

Design follows the house. Smooth stucco, clay tile roofs, deep-set windows and simple massing make an ADU read as part of the original property. Simple casement or divided-lite windows, plain doors and a tile roof pitched like the main house's do more for the review than added ornament. Preservation guidance generally favors new work that is compatible with the old house but still reads as new, so we avoid copying every historic detail.

Parking and Transit for Carthay ADUs

State law bars ADU parking requirements in an architecturally and historically significant historic district, within a half-mile walk of public transit, and for ADUs created inside existing structures. Carthay can hit more than one of those exemptions at once. The D Line extension's Wilshire/La Cienega station opened in May 2026 at Carthay's western edge, and much of the neighborhood is within walking distance of Wilshire.

We confirm which exemption applies to the specific parcel, but in practice most Carthay ADUs carry no parking requirement. Garage stalls lost to the project stay lost; nobody can make you rebuild them. The backyard can then go to living space and garden instead of a paved parking pad. We note it in the permit set.

• Historic district parking exemption
• Half-mile transit exemption near the new D Line stations
• No parking for conversions of existing structures
• No replacement of converted garage spaces

Building in a Preserved Neighborhood

LADWP provides water and power in Carthay. Older houses often have original sewer laterals and small electrical services, so we camera the lateral and run a load calculation early. Service upgrades may need a new meter location, and in an HPOZ the placement of exterior equipment such as meters, heat pump condensers and panels can matter to the preservation review.

Streets are level and access is good. The bigger construction consideration is neighbors: lots are close together, many residents have lived here for decades, and a preserved neighborhood notices dust, noise and parked trucks. We keep the site contained and the schedule visible. Trucks are scheduled outside school and commute peaks where possible.