Solar by Roof Type in Los Angeles

This page is the map. It sets out what we see across our own installed base, what changes by roof type and what does not, and where to go for the detail on each.

Two-thirds composition shingle, a quarter tile, one in nine flat, and metal barely present.

This is our project set, not a census of Los Angeles housing. It reflects the neighborhoods where we have worked. Read the methodology section below before treating any of these proportions as a description of the city.

Tile skews outward. Most of our tile roofs sit in SCE territory — the outer valleys and the newer master-planned tracts. Santa Clarita alone accounts for 23 of them, with Simi Valley, Palmdale and Thousand Oaks behind it. Concrete tile was the default on a great deal of suburban construction from the 1970s onward.

Flat skews inward. Low-slope roofs concentrate hard in LADWP territory and the city proper: 15 in Los Angeles itself, 4 in Burbank. That is the signature of the older urban core and mid-century modernist housing, plus duplexes, additions and ADUs.

The practical consequence: a Santa Clarita homeowner and a Los Angeles homeowner are usually having two different conversations, because they usually have two different roofs.

• Composition shingle — flat rectangular tabs in overlapping courses, usually gray, brown or black, with a slightly granular surface. Architectural versions look thicker and more textured than the older three-tab pattern. If the roof looks like overlapping paper-thin rectangles, this is it.
• Tile — repeating curved or flat units laid in ridged rows, typically terracotta, brown or gray. Concrete tile is heavier and more uniform; clay is usually redder and often has a deeper barrel curve. Both read as rows of separate pieces rather than a continuous surface.
• Flat or low-slope — no visible pitch from the street, often with a parapet wall around the edge. The surface is a continuous membrane, gravel, or a coating rather than individual pieces. Common on mid-century houses, duplexes, additions and ADUs.
• Standing-seam metal — long vertical panels running from ridge to eave with raised seams between them at regular spacing. Unmistakable once you know to look for the raised lines.
• Metal shingles or corrugated panels — also metal, but a different product with different rules: shingles imitate tile or slate in small units; corrugated panels have visible exposed fasteners in rows.

If the roof carries two of these at once — a flat section over an addition, a pitched section over the original house — treat them as two roofs. They frequently follow different rules, and the cool-roof requirement in particular can apply to one and not the other.

Two rows in that table are worth pausing on.

The weight row explains most of the difference between tile and shingle. California's structural screening assumes a tile assembly weighs twice what a shingle assembly does, and that assumption costs roughly 13 percent of allowable rafter span for identical framing.

The pathways row is the biggest single geometric difference. A roof at 2:12 or below is exempt from the fire access and ridge setback requirements entirely, which frees up a great deal of usable area on flat roofs.

• Equipment listings (R329.3.1) — modules to UL 1703 or UL 61730-1/-2; inverters to UL 1741; mounting systems to UL 2703; BIPV to UL 7103.
• Structural obligations (R329.4.1, R329.4.1.1) — the roof must carry the system, with two separate load cases for the covered portion.
• Penetrations (R329.4.3) — flashed and sealed per Chapter 9, wherever they exist.
• Fire classification (R902.4, R907.4) — the rooftop system must be listed to UL 2703, and the rating belongs to the assembly, not the panel.
• Emergency escape openings (R329.6.3) — panels may not sit on the roof below a bedroom egress window, and a 36-inch pathway must reach it.

One note on citations, because it affects nearly everything published on this subject: in the 2025 California Residential Code, solar energy systems are Section R329. Material citing R324 is working from the 2022 edition — in the current code, R324 is Glazing.

1. Will it screen through structurally, or need an engineer? Decided by layer count, rafter size and spacing, span and visible condition — all measurable in an afternoon.
2. What happens at the next re-roof? Cool-roof requirements, tear-off rules and underlayment life are all decided then, and they are cheaper to plan for than to discover.

By roof type

• Composition shingle roofs and solar — the default case: code minimums, the 2:12–4:12 double underlayment rule, and the timing decision.
• Flat and low-slope roofs and solar — the 2:12 exemption, ballast versus mechanical attachment, and membrane warranties.
• Standing-seam metal roofs and solar — mounting without roof penetrations, and the conditions on that.
• Tile is covered in depth in our existing guide, Solar Panels on Clay Tile Roofs in SoCal.

By question

• Can your roof carry the panels? — the state's model structural checklist, with the anchor spacing and rafter span tables and three worked examples.
• How a solar mount is sealed — what the code requires at a penetration, the three sealing methods, and four questions for an installer.
• Three warranties, one leak — who pays to remove an array for roof warranty work. GAF and Owens Corning answer this differently.
• Roof fire class, hazard zones and the 2025 WUI code — what changed in January 2026 and after the maps were redrawn.
• The cool-roof rule most homeowners meet only when they re-roof — the requirement that reaches more climate zones on a replacement than on a new house.
• Do solar panels make a roof hotter or cooler? — the measured answer, and what it means for attic ventilation.

Related existing guides

• Replace your roof before installing solar?
• Solar panel removal and reinstall for a re-roof
• Do solar panels damage your roof?
• How much usable roof space do you need for solar?

What the dataset is. Records of our own completed solar installations in the Los Angeles area, drawn from project files. It is not a survey, not a sample of Los Angeles housing, and not a public dataset.

How a project is counted. One record is one completed installation at one address. Jobs spanning multiple addresses are recorded separately; a single address with more than one phase of work counts once.

The funnel. 440 project records → 365 with the roof covering type recorded, which is the basis of every roof-type figure on this page → 320 of those additionally matched to a Title 24 climate zone by ZIP, which is the basis of the cool-roof figures elsewhere in the cluster. The 45-roof difference is records without a usable ZIP.

Field completeness, stated honestly. Across the 365: roof type and electric utility are recorded for 100 percent; ZIP for 89 percent; installed system size for 38 percent; panel counts for 20 percent; installation year for 53 percent. We publish no price figures from this dataset — the field is effectively empty, and any cost figure we quoted from it would be invented.

Because of that unevenness, figures are always given with their base. The roof-type distribution rests on all 365. A median system size by roof type rests on far fewer, and where we give one, the number of projects behind it is stated next to it.

External data joined. Title 24 climate zones come from the California Energy Commission's official Building Climate Zones by ZIP Code file (2,694 ZIPs), joined on the project ZIP. Note that Title 24 building climate zones are a different system from USDA plant hardiness zones, which is a common source of published error.

Data cut-off: 1 September 2026.

Limitations. The set reflects where we have worked — weighted toward the San Fernando Valley and toward LADWP and SCE territory. It under-represents parts of Los Angeles County where we have done little work, and it says nothing about roofs that never had solar considered. It is evidence about our own projects, useful because it is specific and documented, and it should not be read as a description of the housing stock.

Separately: across the site we cite "1,000+ mapped LA installs", a larger figure drawn from our full project record. The 365 here is a smaller, better-documented subset — those where the roof covering was recorded. The two numbers describe different things and should not be combined.

• California Residential Code 2025 (Title 24, Part 2.5): R329 (solar energy systems — listings, structural, penetrations, access and pathways, emergency escape openings), R902.4 / R907.4 (UL 2703 fire classification), R905.2.2, R905.3.2, R905.9–R905.14, R905.10.2 (minimum slopes by covering), R908.4 (recover permissions and prohibitions).

Figures on this page come from the primary sources below and, where noted, from Cali Energy calculations using the stated assumptions. Rates, incentives, and program terms change; each was verified September 1, 2026.

1. California Energy Code (Title 24, Part 6) 2025: §150.2(b)1Ii and §150.2(b)1Iii(a) — re-roof cool-roof requirements by climate zone, alternatives…
2. California Solar Permitting Guidebook, 4th Edition, Part 3 — structural screening criteria, anchor spacing and rafter span tables, and the 10 psf…
3. California Energy Commission — Building Climate Zones by ZIP Code
4. California Building Standards Commission — 2025 Title 24 published 1 July 2025, effective 1 January 2026