Signs You Need a New Roof: What to Check and When

This page stops at the phone call, so it doesn't trace leaks, read ceiling stains in detail, or cover roof lifespans, prices or insurance; once the roof has been inspected, roof repair or replace picks up the decision. The parts of a roof guide names each layer mentioned here.

• Roofline. The ridge and eaves should run straight. A sag, or a dip in the middle of a slope, is a sign about the deck or framing, not the covering.
• Shingles. Missing or torn pieces, lifted tabs, curling edges, cracks, and bald patches where darker asphalt shows through.
• Tile. Cracked pieces, tiles slipped out of line, gaps.
• Flashing at the chimney, walls and vent pipes: rust, lifted edges, gaps, or sealant smeared over the same spot again and again, which can mean it has leaked before.
• Gutters. Granules piling up, or pieces of shingle or tile.
• Fascia and eaves. Peeling paint, dark streaks, swollen or rotted wood.
• Flat sections. A patio cover, garage or addition you can see from an upstairs window: standing water long after rain, blisters, cracks, patches.

After Santa Ana winds, walk the yard first. Pieces of shingle, tile or flashing on the ground tell you where to point the binoculars.

• Daylight. Turn the attic light off during the day. Light at roof vents, ridge vents and vented eaves is normal; light through the roof boards themselves is not.
• Water. Wet spots, drips, dark stains or soft wood, especially around the chimney, vent pipes, skylights and valleys. Look during a rain or right after one.
• Insulation. Wet, matted or stained patches, and a musty smell.
• Shape. Boards bowing down between rafters, or rafters that sag.
• Nails. Rusty nail tips poking through the deck can point to moisture building up in the attic, often a ventilation problem; attic heat and roof ventilation covers that side.

A dry, old stain may be from a leak fixed long ago. Mark its edge in pencil and look again after the next rain: if it has spread past the line, the leak is still active.

What to photograph for the roofer

1. Each slope from the ground, wide, then zoomed in on anything that looks wrong, with a landmark such as the chimney in the frame.
2. In the attic: stains, wet spots or daylight lit by the flashlight, plus a wider shot showing where they are.
3. Ceiling stains, with the date you first noticed them, and again after the next rain.
4. Gutters holding granules or pieces of covering.
5. The roof edge, zoomed in, if you can see it from the ground: it can show how many layers are on the roof.

Add roughly how old the roof is, what repairs it has had, and whether leaks show in every rain or only in wind-driven rain.

Asphalt shingle

Curling, cracks and bald patches across a whole slope usually point to shingles wearing out; the same damage in one spot after wind points to that spot. Santa Ana winds lift and tear tabs, and a lifted tab may no longer be sealed down even after it falls back flat. Buckling, a wavy or ridged surface, usually starts under the shingles, as the ARMA section below explains.

Clay and concrete tile

A tile roof can look fine from the ground while the underlayment under it has failed. The tile is the outer layer; the underlayment is what keeps water out of the house, and whole, well-seated tiles don't prove that layer is sound. So a leak under good-looking tile is a sign to act on. A trail of broken tiles often marks where someone walked across the roof.

When the tile is sound and the layer under it isn't, the tile can usually go back on over new underlayment and flashings; roof repair or replace explains that job, a lift-and-relay, and the code behind it.

Flat and low-slope

Low-slope roofs show trouble as water and as changes in the surface: standing water long after rain, blisters, cracks, split seams and bare spots. Standing water can point to a sagging deck or blocked drains. Water that gets in can travel between the layers, so a leak inside may show up away from the damage. Many Los Angeles houses have a low-slope section even under a pitched main roof: a patio cover, garage, porch or addition. Re-roofing low-slope roofs, including under solar has its own guide.

• Moisture in the deck shows as distortions along the joints of the deck panels or boards.
• A lack of proper attic ventilation contributes to deck movement.
• Structural deficiencies, or seismic or foundation effects, produce obvious, large disruptions.
• Isolated distortions can also come from nails not driven flush or foreign material under the shingles.

So buckling is a sign about what's under the shingles, which is why the inspection should include the attic. Buckling that lines up with the edges of the deck panels fits ARMA's description of moisture in the deck, and a large, sudden disruption after an earthquake is a structural question to call about right away.

• Two layers already on the roof. At the roof edge you can sometimes see two sets of shingle edges, one on top of the other. The 2025 California Residential Code (CRC 2025, R908.4) does not permit another covering over a roof that already has two, so the next shingle roof usually starts with a tear-off.
• Solar planned soon. Re-roofing under panels means taking them off and putting them back, so settle the roof first; whether to replace the roof before solar covers the timing.

Call right away:

• Water coming in during rain, so the roof can be covered before more falls.
• A new or growing sag, or cracks opening in the ceiling under it.
• A large, sudden change in the roof after an earthquake.

Keep people out of the rooms under a sag. A sag or earthquake damage is a structural question, and a structural engineer or the building department may need to see it too.

Call this week:

• Water inside after rain: a new or growing ceiling stain, wet boards or insulation in the attic. A stain that appears in dry weather more often comes from a plumbing line or the AC; check those first.
• Daylight through the roof boards.
• An old sag that hasn't changed.
• Shingles or tiles missing or torn after wind, above all with rain coming.
• A leak on a tile roof, however good the tile looks.

Don't climb up to tarp a leak yourself; a roofer can cover it until the repair.

Book an inspection this season:

• Curling, cracking or buckling shingles, or bald patches, with no leak yet.
• Cracked or slipped tiles, rusted flashing, or peeling paint on the fascia.
• Standing water, blisters or cracks on a flat roof, with nothing coming through yet.
• A musty attic with nothing visibly wet.
• An older roof with no visible signs, or one that has needed repair after repair: wear isn't always visible from below, so book one before the rainy season rather than after a leak.
• A second layer on the roof, or solar in the plans.

If you're not sure whom to call, choosing a roofing contractor in California covers what to check before hiring one.

• Burbank, 2023: the call was a leak on a tile roof that looked fine from the street; the failure was the underlayment and flashings under the tile.
• On three shingle re-roofs, in Granada Hills (2022), Northridge (2023) and Canoga Park (2024), rotten or damaged wood under the old covering came into view only once it was off.

More roofing projects are on our case studies page, and roofing work on its own is on our roofing page. We're licensed for it: CSLB #1032379, C-39 Roofing, B General Building and C-10 Electrical.

Code sections, rules and figures on this page come from the primary sources below. Codes, local requirements and product terms change; each was verified September 29, 2026.

1. Asphalt Roofing Manufacturers Association, Plain Facts About Buckled Shingles
2. Asphalt Roofing Manufacturers Association, Application of Coatings or Rejuvenators on Asphalt Shingles After Installation
3. California Residential Code 2025, Chapter 9 Roof Assemblies, R908 (UpCodes)