Choosing a Roofing Material in Southern California

The mix shifts with the utility. In LADWP territory, which takes in the City of Los Angeles, shingle outnumbers tile more than four to one (137 to 32), and flat roofs (27) nearly match tile. In SCE territory the count is 89 shingle, 53 tile and only 7 flat. A few roofs are in other utilities' areas, so the two territories don't add up to 365.

Tile leans toward the outer valleys and the newer master-planned tracts in SCE territory: Santa Clarita alone has 23 of the 85 tile roofs, followed by Simi Valley, Palmdale and Thousand Oaks. Flat roofs gather in the older urban core, with 15 at a Los Angeles mailing address and 4 in Burbank.

These are our projects, not a census of Los Angeles housing. Still, they hint at where a choice starts: in a tile tract, the HOA or the street may favor keeping tile, and an older house in the core is more likely to have a flat section that neither shingle nor tile can cover.

Weight classes are relative. The Solar Permitting Guidebook's screening assumptions for tile and non-tile roofs, below, are the only published figures used here; for metal, synthetic and membrane systems, the product's data sheet gives the weight.

Slope

Slope is rise over 12 inches of level run, so a 4:12 roof climbs 4 inches for every foot. The code sets a minimum for each covering, which makes slope a filter rather than a preference:

• Flatter than 2:12: no asphalt shingle and no tile. The options are low-slope membranes, built-up roofing and standing-seam metal (all down to ¼:12), or lapped metal panels with lap sealant (down to ½:12). The full table by material is in minimum roof slope by material.
• From 2:12 to 4:12: shingle with a double layer of underlayment; tile from 2½:12, also with a double layer. Metal roof shingles, stone-coated steel among them, and wood shakes need 3:12.
• Steeper than 4:12: every steep-slope covering qualifies, and the other constraints decide.

One house often needs two coverings: shingle or tile on the main roof, and a low-slope system on a nearly flat addition, patio cover or garage.

Weight and the framing

The covering is a large part of the load the rafters or trusses were sized for. For its structural screening of rooftop solar, the California Solar Permitting Guidebook (4th edition) assumes a roof assembly weight of 10 pounds per square foot for a non-tile roof (asphalt shingle, wood shingle or wood shake) and 20 pounds per square foot for a tile roof (clay or cement tile), so under tile the same rafters get shorter allowable spans. Can my roof support solar panels explains how framing is checked.

• Going heavier (shingle or shake to tile): have the framing checked before you settle on tile.
• Going lighter (tile to shingle, metal or a lighter tile-look product): the new covering takes weight off the framing.

Shingle and tile alike go on a solid deck of lumber sheathing or wood structural panels (CRC 2025, R905.2.1 and R905.3.1); parts of a roof shows where the deck sits. Wood shakes can sit on spaced boards; if an old shake roof was built that way, it has to be sheathed solid before shingle or tile goes on.

Weight shows up in the permit too. In the City of Los Angeles, a re-roof over solid sheathing with a Class A or B covering weighing less than 6 pounds per square foot gets an express permit with no plan check; a heavier covering doesn't qualify for that route. Permits are covered in choosing a roofing contractor.

Fire zone

The 2025 California Wildland-Urban Interface Code applies, in cities and county areas, to High and Very High Fire Hazard Severity Zones (the City of Los Angeles included), to all zones in State Responsibility Areas, and to any area a city or county has designated as a wildland-urban interface. Inside them, the roof has to be a Class A assembly (section 504.2). What that changes in the choice:

• Tile and metal on a wood deck both need a tested assembly. The code accepts a short list of assemblies as Class A without testing, and for tile and metal sheets and shingles it applies only on a noncombustible deck (slate qualifies over a wood deck only over ASTM D226 Type II underlayment). Houses here usually have wood decks, so tile, standing-seam and stone-coated steel go on as tested, listed Class A assemblies; ask the roofer which one they are building.
• Profiles with an air space over a wood deck, as tile and many stone-coated steel profiles have, also need the extra details of 504.2.1, described in the parts of a roof guide.
• No wood roofs in City of Los Angeles zones, fire-retardant-treated included.
• Outside the zones, a floor: replace more than half the roof within a year, and the whole covering must be Class C or better (CRC 2025, R902.1.2).

Check the exact address on the Office of the State Fire Marshal's zone maps and on the zone map your city or county keeps. Zone lines run through neighborhoods, so a street name or a postal code won't settle it. When a re-roof has to meet these rules is covered in fire class and the 2025 WUI code, and how tile, metal and shingle compare in a wildfire, with the details that keep embers out, in fire-resistant roofs in Los Angeles.

Summer heat and the cool-roof rule

Heat enters the choice mostly through color. Under the California Energy Code (Title 24, Part 6), replacing more than half the roof triggers the cool-roof requirement, depending on the climate zone: zones 4 and 8 through 15 for steep-slope roofs, zones 4 and 6 through 15 for low-slope sections, and most of the Los Angeles basin and the San Fernando Valley falls in zone 9. Even with its exceptions and alternatives, the rule can narrow the colors and products available, so check a product against it before you fall for a shade. The cool-roof requirement on a re-roof has the details, and how much color changes the heat is in the best roof color for Los Angeles heat.

Solar now or later

If panels are likely within a few years, choose the covering with them in mind and re-roof first; a roof that wears out under an array means taking the panels off and putting them back. By covering:

• Asphalt shingle: the most straightforward mounting; see solar on composition shingle roofs.
• Clay or concrete tile: workable but slower, since tiles crack underfoot and each mount means working around or replacing a tile; see solar on clay and concrete tile.
• Standing-seam metal: clamps on the seams can hold panels without drilling into the roof, under the conditions in standing-seam metal roofs and solar.
• Low-slope membranes: racks tilt the panels up off the membrane; see flat and low-slope roofs, including under solar.

Weighing a solar roof covering against panels on a conventional roof? Tesla Solar Roof vs solar panels compares the two, and solar by roof type sets every covering side by side.

HOA and historic district rules

An HOA or a historic district can restrict color, material and even tile profile, so get the approved list from the HOA's architectural committee or the city's historic preservation office before you commit to anything. What a California association may and may not require, and how it has to handle your request, is in what an HOA can require when you replace your roof.

Budget

Price decides among the materials that survive the steps above, not before them. Asphalt shingle is usually the least expensive covering and simple to repair piece by piece; tile, metal and tile-look products generally cost more up front. The constraints add costs of their own: framing work before a move to tile, solid sheathing over spaced boards, fire-zone assembly details, and the care tile needs underfoot. Sound tile already on the roof can often be relaid over new underlayment, with new pieces only for breakage; in a fire zone, relaying half the roof or more brings in the fire-zone assembly rules.

Asphalt (composition) shingle

A fiberglass mat coated with asphalt and surfaced with mineral granules. Three-tab shingles are one flat layer cut into even tabs; architectural, or laminated, shingles bond two layers for a thicker, textured look. Light, usually the least expensive, easy to repair and the easiest base for solar, it covers 239 of the 365 solar homes in our count. How 3-tab, architectural and designer shingles compare in build, wind and warranty is in architectural vs 3-tab vs designer shingles.

Concrete and clay tile

Concrete tile is cement-based and comes in flat and curved profiles; clay tile is fired clay, the traditional look on Spanish and Mediterranean houses. Both are heavy. The tile itself is durable, but the underlayment beneath it ages, and renewing that layer, often by lifting and relaying the same tile, is what a tile roof eventually needs. If tile went on later over framing meant for a lighter roof, have that checked before the next re-roof.

Standing-seam metal

Long panels running from ridge to eave, joined at raised seams. It's light, good down to ¼:12, and suited to clamp-mounted solar, under conditions. It's rare among the 365 solar homes in our count (1 of 365), so weigh how it will look on the street and what the HOA allows. How it compares with screw-down metal panels on slope, upkeep, fire listing and the coast is in standing seam vs exposed-fastener metal roofs.

Stone-coated steel

Steel panels coated with stone granules and formed to look like tile or shake, without tile's weight. The code minimum for metal roof shingles is 3:12, and the product's listing sets the details. Solar needs mounts made for the profile.

Synthetic slate and shake

Molded composite or polymer products that imitate slate or wood shake at less weight. Slope, fire class and solar mounting come from the product's listing, so ask to see it. In a fire zone they can give a shake look where wood isn't allowed, if the assembly is tested Class A. Two makers' products, weights, fire assemblies and warranties are compared in synthetic slate and shake roofs.

Wood shake and wood shingle

Split or sawn wood, with a 3:12 minimum for shakes. Not permitted anywhere in the City of Los Angeles, treated or not (LABC 91.1505.1); elsewhere, outside fire zones, check any wood product's fire rating against the Class C rule above.

Flat and low-slope systems

Single-ply membranes (TPO and PVC), modified bitumen, built-up "hot mop" roofing, and coatings over an existing system; membranes and built-up roofing go down to ¼:12. Forty of the 365 solar homes in our count had flat or low-slope roofs, concentrated in the older urban core. Choosing among these systems is covered in flat roof options for Los Angeles homes, and solar on them in flat and low-slope roofs, including under solar.

Code sections, rules and figures on this page come from the primary sources below. Codes, local requirements and product terms change; each was verified October 7, 2026.

1. California Residential Code 2025, Chapter 9 Roof Assemblies (UpCodes)
2. California Wildland-Urban Interface Code 2025, Chapter 5 (UpCodes)
3. LADBS, Fire Hazard Severity Zone Supplemental Checklist (2025 CWUIC), revised March 27, 2026
4. California Solar Permitting Guidebook, 4th Edition
5. California Energy Code (Title 24, Part 6) 2025, cool-roof requirements (Cool Roof Rating Council summary)
6. Office of the State Fire Marshal, Fire Hazard Severity Zones