Should I repair or replace my roof in Marin County?

When is a repair enough?

A repair usually makes sense when the damage is in one place and the rest of the roof is sound: a cracked pipe boot, a few missing shingles after a windstorm, flashing that has pulled away at a wall or chimney, or a single slipped tile. Ask the roofer to photograph the problem and the surrounding roof so you can see the difference.

When does replacement make more sense?

• Shingles are curling, cracking or shedding granules across most slopes.
• Leaks show up in different places each winter.
• The deck feels soft or sags in more than one area.
• The roof is at or past the typical life for its material (see the table below).
• Repairs have been made several times in the last few years.

Can a new roof go over the old one?

Sometimes, but California's Residential Code limits it. Under Section R908, a roof recover isn't permitted where the existing roof is water-soaked or too deteriorated to serve as a base, where it is slate, clay, cement or asbestos-cement tile, or where it already has two or more layers of any roof covering. In those cases everything comes off down to the deck.

How old is too old?

Expected life depends on the material, installation and maintenance. InterNACHI's estimated life expectancy chart gives these guidelines:

Source: InterNACHI Standard Estimated Life Expectancy Chart. These are guidelines under normal conditions, not guarantees.

What's typical for homes in Marin County?

San Rafael's median home dates to 1968 and Novato's to 1975, while older pockets in Mill Valley, Sausalito and the Ross Valley predate both. Tract neighborhoods in Terra Linda and Novato often carry 1990s or 2000s shingle roofs now reaching the end of a typical architectural shingle's life, and older hillside homes can have layers, complex valleys and past wood-shake roofs that raise fire-rating questions.

How do insurance and roof age factor in?

Insurers look at roof age and condition when they decide whether to renew a policy. Starting January 1, 2028, California's SB 1301 bars an insurer from refusing or nonrenewing a policy solely because of roof age if you pay for an independent inspection that confirms at least five years of useful life remaining. Read our insurance guide for the details. Weighing timing around this winter's storms? See replacing before or after El Niño.