Should a 20 Year Old Roof Be Replaced?

It Depends on What Is on Your Roof

We see a lot of 20 year old roofs in Ontario. Some are done. Some have another 10 years in them. The material is what decides which one you have.

The InterNACHI life expectancy chart lists a 3 tab asphalt shingle roof at about 20 years and an architectural shingle at about 30 (InterNACHI). It puts clay or concrete tile at 100 years or more, and metal at 40 to 80. The same chart warns that hot climates cut asphalt shingle life by a lot.

Other sources run shorter. The Roof Maxx learning hub, updated July 29, 2026, lists asphalt shingles at 15 to 20 or more years (Roof Maxx). These are guides for normal wear, not promises. A roof that was installed badly can fail at 12. A roof that was done right can beat its number.

So the first question is not how old. It is what kind. Look at the chart below, then find your roof on it.

A 20 Year Old Shingle Roof

If your house has 3 tab shingles and they are 20 years old, plan on replacing them. That roof is at the end of its rated life (InterNACHI), and Ontario heat is hard on asphalt.

If you have architectural shingles, the thicker kind with a layered look, you may have time left. Twenty years is about two thirds of the 30 year rating on the InterNACHI chart. Check the signs below before you decide.

We see the same wear over and over on older shingle ranches near downtown Ontario, Montclair and Upland. Edges curl. Grit washes into the gutters. Shingles crack and blow off in Santa Ana winds. Once you see those on more than a few spots, patching starts to cost more than it saves.

A roofing guide that ranks near the top for this question says a 20 year old roof does not have to be replaced just for its age (Dr. Roof). We agree. But on a shingle roof in our heat, 20 years is the point where you stop waiting and start planning.

A 20 Year Old Tile Roof Is a Different Story

Most tract homes in Ontario Ranch, Eastvale, Chino and Rancho Cucamonga wear concrete tile. On those roofs, the tile is rarely the problem. The paper under it is.

Tile sheds most of the water. The underlayment below it is a second barrier that catches wind driven rain and water from broken tile, as the Tile Roofing Institute's technical director explained (Eagle Roofing).

That paper does not last as long as the tile. A reserve study engineer who tracks California roofs puts tile underlayment at a useful life in the 30 year range (Association Reserves). So a 20 year old tile roof is at about two thirds of its paper's life, while the tile itself may have decades left.

That is why a 20 year old tile roof usually does not need a new roof. It needs someone to lift a few tiles and look. If the paper is still flexible and dry, you may be fine for years. If it is brittle and torn, the fix is a re-lay. The tile comes off, new underlayment goes on, and the same tile goes back. The same engineer plans for about 5 percent breakage when tile is lifted and reset (Association Reserves). Our tile roofing page shows how a re-lay works.

Our post on roof leaks in heavy rain explains why a tile roof that looks fine from the street can still leak.

What Your Insurance Company Thinks

Many owners find this out from a letter. In May 2026, Insurance Business reported on the underwriting rules of 20 large California home insurers (Insurance Business). Farmers may limit asphalt roofs older than 15 years to actual cash value instead of full replacement cost. Mercury and Wawanesa generally will not insure roofs older than 25 years, with exceptions for tile and slate.

So a 20 year old shingle roof can already cost you coverage with some carriers, even if it does not leak. A 20 year old tile roof is usually treated better, but an aerial photo cannot see worn paper under good tile.

We cover the full picture, including nonrenewal notices and the new law that starts in 2028, in our post on roof age and home insurance in California. If a renewal letter is what made you ask this question, read that one next.

Repair, Re-Lay or Replace

Every 20 year old roof we look at ends up on one of three paths. This is how we would sort yours.

Repair when the damage is in a few spots. A cracked tile, a lifted pipe boot, a worn valley or a few blown shingles. The rest of the roof is sound. See our roof repair page for what that covers.

Re-lay when it is a tile roof, the tile is mostly sound, and the underlayment is brittle, torn or leaking in more than one place. You keep the tile and replace the paper.

Replace when it is a shingle roof with wear across most of it, when you have had repeat leaks in different spots, when the deck is soft or sagging, or when your insurer will not renew because of the roof.

The quickest way to know which path you are on is a roof inspection with photos of what is under the tile or shingles. Age gets you to call. Photos tell you what to do.

If your roof in Ontario or the west Inland Empire is coming up on 20 years, call Ontario Roofing at (909) 404-9464 for a free written estimate with photos of your roof.