Residential Solar Permits in Unincorporated LA County: 36,175 EPIC-LA Records, 2020–2026

Coverage. EPIC-LA is the permit system of LA County Public Works. This study uses its records for unincorporated county areas — communities without their own city government, such as Altadena, East Los Angeles, Hacienda Heights, Rowland Heights, Stevenson Ranch, Castaic, Quartz Hill, Acton and Topanga. The City of Los Angeles (LADBS) and cities with their own building departments are not included; for the City of LA see LADBS solar permits. Counts are permit applications by month filed, not finished installations.

Three moments stand out. In March and April 2023 applications rose to 858 and 809, up from 475 in January, just before SCE customers’ new interconnection applications moved from net metering (NEM 2.0) to the Net Billing Tariff on April 15, 2023 (NEM 3.0 explained); most of unincorporated LA County is SCE territory. In late August 2023 the county opened its Express path for standard residential systems, with and without storage, close to the September 30, 2023 deadline in California’s SB 379 for automated solar permitting (California Energy Commission). And there was no rush before the federal 25D credit ended: July–December 2025 averaged 288 applications a month against 353 in January–June, because the credit required a system to be placed in service by December 31, 2025, and a late-2025 permit was usually too late (the 30% credit ended).

The biggest spike, March–April 2022, is not a countywide shift: 58% of those 2,051 filings were in the Santa Clarita Valley (against 23% in the rest of 2022), and one description template accounts for 37% of them (against 5% in the rest of the year) — the signature of a single high-volume program filing in bulk.

New systems on existing homes are 94% of all records and drive the trend. The other three types move on their own: new homes and ADUs rose from 62 in 2020 to 451 in 2025, since California’s Title 24 code requires solar on most new homes (does a new ADU need solar?); the 2025 rise is concentrated in the San Gabriel Valley and foothills (287 of 451), the region that includes Altadena. Remove-and-reinstall permits went from 4–13 a year to 153 in 2025 — see below. Solar roof tiles and solar shingles (Tesla Solar Roof, GAF Timberline and other building-integrated PV) were 45 applications in 2020 and 13 in 2025, under 2% of new systems in any year (solar roof vs. panels).

Part of the jump is how batteries are recorded: the Express path has a separate “with ESS” category, while standard permits mention a battery only in the description. But the shift shows up on the standard path too, where nothing changed in the recording: 7–9% in 2020–2023, 33% in 2024 and 33% in 2025. On Express, 83% of 2025 filings included storage. Under net billing, solar exported at midday earns far less than power used in the evening, so storing it pays more — see do I need a battery with NEM 3.0 and what NEM 3.0 did to California solar.

On Express, the permit is issued at filing: 86–91% the same day, median 0 days. On the standard path the median wait fell from 21 days in 2020 and 14 in 2022 to 4 in 2025 and 2 so far in 2026. The permit is no longer the slow step. From permit to final inspection the median was 106 days for 2024 Express filings and 179 for standard ones; that span includes installation, any main panel or utility work and scheduling the inspection, not county review alone. For the full sequence through utility approval, see permit to PTO timeline in Los Angeles.

Nine in ten applications get a permit, and 8–16% are voided, canceled or left to expire. The notable group is the permits that were issued and never closed: for applications filed in 2020–2023, 14–19% of issued permits still show “Issued” with no final inspection in the county record years later. Some are systems that were installed but whose final inspection was never requested or recorded; some were never built. The record alone cannot tell which. An open permit can come up when a home is sold or refinanced, so if your system is a few years old, look it up on EPIC-LA: it should say Finaled. Common reasons a final fails are covered in why solar inspections fail.

Permits to take an existing array off and put it back, almost always for a new roof, were 4–13 a year in 2020–2023, then 71 in 2024, 153 in 2025 and 123 in January–August 2026. 73% of the 2025 permits mention the re-roof, and the number citing a linked building permit rose from 2 in 2024 to 22 in 2025 and 33 in January–August 2026. The record cannot show whether more homeowners are re-roofing under solar or whether more of these jobs are now permitted separately; either way, a re-roof under existing panels is a permitted solar job. See solar removal and reinstall for a roof replacement.

Every region fell. The Santa Clarita Valley fell furthest, by 65%, partly because its 2022 total includes the spring 2022 bulk filings. The Santa Monica Mountains, coast and Palos Verdes fell least, by 25%. Since 2023 the San Gabriel Valley and foothills have filed the most new systems of any region.