Winnetka, CA · January – March 2024 · LADWP / LADBS
Six and a half kilowatts on concrete tile.
A 6.5 kilowatt AC-CEC array on a Winnetka house with a concrete tile roof — black modules across two planes, with every attachment flashed through the tile.
Mounting on concrete tile is slower than mounting on shingle and the attachment detail is what decides whether the roof stays watertight. The array sits flush, and the tile around it goes back.
At a glance
- System
- 6.5 kW AC-CEC
- Modules
- Mission Solar 395 W
- Electronics
- Enphase, per module
- Combiner
- Enphase IQ Combiner 4
- Roof
- Concrete tile, two planes
- Application to PTO
- Six weeks
- Battery
- None
- Utility / AHJ
- LADWP / LADBS
The story
A 6.5 kilowatt AC-CEC array on a Winnetka house with a concrete tile roof. Mission Solar 395-watt modules, Enphase electronics under every one of them, an IQ Combiner 4 where the array comes together.
Tile is the part of this job that takes the time. Every attachment point means lifting tile, setting a flashed mount to the rafter and bringing the tile back over it. Whether the roof stays watertight depends on the whole assembly — the mount, the flashing, the underlayment beneath it and the condition of the roof it goes into — not on any single part of it.
The array runs across two planes rather than one block, which is normal on a house of this shape. In this Enphase design each module has its own electronics, so the two planes produce on their own schedules and each position is monitored separately.
The calendar was ordinary and quick: interconnection application and fee at the end of January 2024, site evaluation the next day, inspections requested at the end of that week, building department release and interconnection approval on the eighth of February, permission to operate on the seventh of March.
How it ran
| 25 January 2024 | Interconnection application filed; utility fee paid |
|---|---|
| 26 January 2024 | Utility site evaluation completed |
| 29 January 2024 | Inspection requested |
| 8 February 2024 | Building department release; interconnection review completed |
| 7 March 2024 | Permission to operate |
The calendar runs from the interconnection application to permission to operate.
What we did
- Mounted the array on concrete tile with flashed attachments set to the rafters.
- Reinstated the tile over every attachment point.
- Split the array across the two usable roof planes rather than forcing one block.
- Installed per-module electronics so the two planes run independently.
- Carried the project from interconnection application to permission to operate in six weeks.
System specifications
| System | 6.5 kW AC-CEC |
|---|---|
| Modules | Mission Solar, 395 W |
| Electronics | Enphase, one per module |
| Combiner | Enphase IQ Combiner 4 |
| Roof | Concrete tile, array across two planes |
| Attachments | Flashed mounts set to the rafters, tile reinstated over them |
| Battery | None |
| Utility / AHJ | LADWP / LADBS |
Is your project like this one?
- Your roof is concrete tile and you have been told solar on it is a problem.
- You are worried about leaks at the attachment points.
- Your roof faces more than one direction.
- You want to know what a mid-size residential system looks like here.
- Your Winnetka property is served by LADWP, while permits are handled by LADBS.
Cali Energy in Winnetka
Winnetka is inside City of Los Angeles boundaries: permits run through LADBS, interconnection through LADWP.
A lot of the older housing stock here carries concrete tile, and mounting on it is a different job from mounting on shingle.
This installation is on the Winnetka projects page alongside the others, and what the work covers is set out on the Winnetka service area page.
- License and classifications: CSLB #1032379
- Official reference for this process: LADBS — plan review and permitting
- Official reference for this process: LADWP interconnection requirements
Frequently asked questions
Can solar be mounted on a concrete tile roof?
Yes. Tile is lifted at each attachment point, a flashed mount is set to the rafter, and the tile goes back over it. It is slower than shingle, and whether the roof stays watertight depends on the whole assembly — mount, flashing, underlayment and the condition of the roof — which is why the attachments are photographed as they go in.
Does tile mounting cost more than shingle?
It takes more time per attachment, and time is what a roof mount costs. What it buys is keeping the roof you have rather than replacing the field under the array.
Why split an array across two roof planes?
Because the roof has two usable planes and they collect sun at different times. In this Enphase design each module has its own electronics, so the two planes produce on their own schedules and each position is monitored separately.
How long did this project take?
Six weeks from the interconnection application on 25 January 2024 to permission to operate on 7 March, with the building department release and the utility's interconnection review both completed on 8 February.
Does Cali Energy install on tile roofs in Winnetka?
Yes — concrete tile, clay tile and composition shingle. Winnetka is inside City of Los Angeles boundaries, so permits run through LADBS and interconnection through LADWP.
What this would look like on your roof
Every number on this page came off a real job in Winnetka, CA — not a brochure. Tell us your utility, your roof and what your bill looks like now, and we will model your own version of it before you commit to anything.
Or call +1 (323) 844-7777 · Cali Energy, Northridge · CSLB #1032379 (B, C-10, C-39) — design, permits, install and electrical under one licensed contractor.
Related
This timeline reflects this property and this permitting path. Updated September 2026.