Northridge, CA · December 2021 – February 2022 · LADWP / LADBS

S-tile on the roof, and a new service on the wall.

Twenty-six modules on S-profile concrete tile, and a new upgraded service with a 200 amp bus to carry them. Nine point six kilowatts on the approved plans.

Two things decide whether a roof can take a given array: the structure under the covering and the electrical service it connects to. On this house the roof was fine and the service was not, so the service was replaced as part of the job.

At a glance

Array

9.62 kW DC — 26 × 370 W

Modules

26 × REC 370 W

Microinverters

26 × Enphase IQ7PLUS

Roof

S-profile concrete tile

Structure

2×4 rafters at 24 in

Service

New, 200 A bus and main breaker

Request to PTO

Four weeks

Utility / AHJ

LADWP / LADBS

The story

The roof here is S-profile concrete tile — the deep wave rather than the flat shake — on a two-storey house with 2×4 rafters at twenty-four inches. That spacing and that profile set how the array attaches: tile lifted along the rail lines, IronRidge attachments into the rafters, each penetration flashed, tile reset over the top.

The electrical side was the larger piece of work. The house got a completely new, upgraded service with a 200 amp bus and a 200 amp main breaker. That is not a cosmetic change: the stucco comes off around the old enclosure, the new gear goes in, the conduit is re-run, and the utility has to release the meter before anything is live.

Before any of that was drawn, the owner had two equipment packages to choose between — one built around a 9.5 kilowatt LG array and one around REC 370 watt modules with Enphase microinverters. The REC package is what went on the roof: twenty-six modules, twenty-six IQ7PLUS microinverters, 9.62 kilowatts DC on the approved plans.

Once the plans were approved the utility side moved quickly. The interconnection request went in on the twelfth of January, the first two progress notices came the next day, the site evaluation was complete inside a week, the installation was released at the end of the month, and permission to operate arrived on the eighth of February — four weeks from request to permission to operate, on a job that included a new service.

How it ran

A new service usually adds weeks. Here it did not.

What we did

• Put two equipment packages in front of the owner before anything was drawn.
• Designed a twenty-six module array for S-profile concrete tile on 2×4 rafters at 24 in.
• Replaced the electrical service with new gear on a 200 amp bus and main breaker.
• Installed twenty-six REC 370 watt modules with one Enphase IQ7PLUS each.
• Carried the interconnection from request to permission to operate in four weeks.

System specifications

Is your project like this one?

• Your roof is S-profile concrete tile and you want to know how an array attaches to it.
• You have been told your service will not carry the array you want.
• You want to compare two equipment packages rather than be handed one.
• You want to know how long a job takes when the service is replaced as part of it.
• Your service has to be replaced before the array can connect.

Cali Energy in Northridge

Frequently asked questions

What is S-tile and does it change the installation?

S-tile is a deep-wave concrete profile. The array attaches the same way as on any tile: tile lifted along the rail lines, attachments into the rafters, penetrations flashed, tile reset. The profile changes the flashing detail, not the principle.

Why did this house need a new service?

The existing service could not carry the array alongside the rest of the house. It was replaced with new gear on a 200 amp bus and a 200 amp main breaker as part of the same project.

Does a service replacement delay the solar?

It adds electrical work and a meter release from the utility. On this project the interconnection still ran from request to permission to operate in four weeks.

How is the system size stated?

By the modules on the approved plans: twenty-six at 370 watts, 9.62 kilowatts DC. That is the figure that can be checked against the plan set and the equipment on the roof. An inverter's continuous AC output is a separate number and we do not blend the two.

Can I see more than one equipment option?

On this project the owner saw two packages before the plans were drawn, one built around LG modules and one around REC with Enphase microinverters. We quote it that way when the roof allows more than one sensible answer.

Does Cali Energy replace electrical services in Northridge?

Yes. Cali Energy holds B, C-10 and C-39 classifications under CSLB #1032379.

What this would look like on your roof

Related

• Same street, same tile, same module. Different job Northridge, CA · 8.51 kW DC · paired case Solar
• The array was already there. The service was the problem Northridge, CA · 10.87 kW AC-CEC · remediation Solar
• Five quotes for the same roof. Then five years of coming back Northridge, CA · 7.4 kW AC-CEC · SolarEdge Solar
• Six and a half kilowatts on concrete tile Winnetka, CA · 6.5 kW AC-CEC · Mission Solar Solar

This timeline reflects this property and this permitting path. Updated September 2026.