The local rules on a Rolling Hills roof

The statewide layer

These are not specific to Rolling Hills, but they apply to it, and several of them are widely got wrong — including by contractors quoting from habit rather than from the current code.

Tear-off waste and where it goes

CALGreen requires 65 per cent of nonhazardous construction and demolition waste to be diverted from landfill — but that chapter applies to additions and alterations that increase a building's conditioned area, volume or size, and a straight re-roof does not. So the state mandate generally does not reach a re-roof.

Local ordinances frequently do, and the state code expressly lets a city be stricter. Plenty of cities capture roofing through their own construction and demolition rules by permit valuation, which can mean a deposit and a diversion report on an ordinary house. Ask the city before the skip is ordered rather than after.

How many layers can stay on

A new covering cannot go over the old one where two applications are already up there, where what is there is water-soaked or degraded past being a sound base, or where the existing covering is slate, clay, cement or asbestos-cement tile. Any of those means a strip to the deck.

Two layers is therefore the practical ceiling, and on an older house nobody knows how many are up there until somebody looks. That is the single most common reason a re-roof price changes after the work starts, and it is a fair reason to ask for the quote to state what happens if a third layer appears.

The right to cancel

A home improvement contract can normally be cancelled within three business days, and within five if the buyer is a senior citizen. Where the contract is to repair or restore residential damage from a disaster or a declared state of emergency, that window is seven business days.

That longer window exists because of what happens on a street after a storm. Nothing has to be signed at the door — and if something was, the clock above is why it is worth re-reading tonight rather than tomorrow.

Fire classification: what is actually required, and where

The statewide floor is a Class C fire-retardant roof covering. That applies to a new roof, to any repair or replacement, and to any existing building where more than half the roof area is replaced within a year — which is every ordinary re-roof.

Class A, the highest classification, is required where the property sits inside a fire hazard severity zone or a wildland-urban interface area, and many cities require it more widely by local ordinance. In practice, across most of south Orange County, Class A is the answer — but it comes from the fire zoning and the local ordinance rather than from a blanket statewide rule, so it is worth confirming for your address rather than assuming either way.

One citation to watch for: since 1 January 2026 the wildfire provisions are their own volume, the California Wildland-Urban Interface Code at Title 24 Part 7. It absorbed what used to be building code Chapter 7A and residential code section R337. Anyone still quoting Chapter 7A is quoting a superseded document.

What a wildfire-zone roof actually has to include

In a mapped fire hazard zone the requirements reach well past the covering, and they are the details that separate a compliant roof from a cheap one. Embers, not flame fronts, are what destroy most houses in a wildfire, and every one of these requirements is about closing a gap an ember could get through.

• A roof assembly meeting Class A when tested to ASTM E108 or UL 790
• On profiled tile, bird stops at the eaves and hip and ridge caps mudded in, so there is no open end for embers to enter
• Valley flashing of at least 0.019 inch (26 gauge) corrosion-resistant metal, over a mineral-surfaced cap sheet at least 36 inches wide
• Noncombustible gutters and downspouts, with an approved means of stopping leaves and debris collecting in them
• Vent screening of noncombustible corrosion-resistant mesh, no finer than 1/16 inch and no coarser than 1/8 inch

The code your roof will be built to

California re-roofs are built to Title 24, the California Building Standards Code. The 2025 edition took effect on 1 January 2026 and applies to any project whose permit application was made on or after that date. If your last roof went on before then, it was built to a different edition, and some of what was acceptable on it is not acceptable now.

This is practical rather than academic. A contractor quoting from memory instead of from the edition currently in force will occasionally price a detail that will not pass — and the inspection comes at the end of the job, not the beginning.