Signs You Need a New Roof

Signs that need attention now

Water getting in

A leak is the sign that cannot wait. The Insurance Institute for Business & Home Safety (IBHS), through its FORTIFIED program, calls water intrusion a worst-case scenario that should be addressed immediately, because it can damage belongings and bring mold. It also gets more expensive by the week. On our roof repair cost guide, a leak caught before it soaks anything costs $150 to $1,000 to fix, $1,000 to $3,000 once water has reached the underlayment, decking or insulation, and $3,000 to $6,000 or more once it reaches the framing.

A leak on its own does not mean the whole roof is finished. A failed vent boot or a flashing gap can leak on an otherwise sound roof. What a leak does mean is that someone needs to find the source now, and tell you what condition the rest of the roof is in.

A sagging or wavy roof

IBHS describes a sagging or wavy roof as a very serious issue, because it points to damaged structural components under the covering, and recommends an immediate inspection. This is not a shingle problem. Sagging roof repair runs $1,000 to $5,000 or more on its own, before any new roof goes on.

Signs of a worn-out shingle roof

These are the signs both IBHS and Owens Corning list for an asphalt shingle roof nearing the end of its life. One of them on a young roof may be a repair. Several on an old roof usually are not.

• Curled or cupped shingles. Edges that lift or tabs that bow upward. IBHS notes this can point to improper installation or poor attic ventilation, which is worth knowing before a new roof goes on over the same attic.
• Bald spots where granules are missing. IBHS says rain, hail, ice and debris wear them away, which leaves places for water to sit and speeds up the shingle’s aging.
• Cracked, torn or missing shingles. Physical damage from weather or impacts, and the easiest sign to spot from the ground.
• Rusted flashing or gutters, and exposed nails. IBHS lists rust as a sign that water and debris are not draining the way they should, and exposed or rusty nails as wear on the fasteners that hold the roof down.

If a storm caused any of this damage, check your homeowners insurance before you pay for a repair yourself. Our guide on whether insurance covers roof replacement explains what a policy pays for.

Signs that are mostly cosmetic at first

Dark streaks. Owens Corning says the dark streaks on many roofs come from naturally occurring airborne algae, and that while they may not harm the shingles, they do not look good. IBHS adds a caution: any inconsistency in roof color over time could have a moisture-related cause, so streaks are worth mentioning to an inspector.

Moss. Moss grows on roof surfaces that get little sun, especially in cool, moist climates. According to Owens Corning, it holds moisture against the roof and, in freezing climates, can damage the granules over time. Brushing it off can damage the top of the shingle and will not stop it growing back, so it is a job to discuss with a roofer rather than attack from a ladder. Some shingle warranties cover algae staining for a limited period; our roof warranty guide explains the terms.

Age: the sign you look up rather than see

Owens Corning lists a roof that is at least 20 years old, or looks old and worn, as a sign on its own, and notes that poor ventilation can age shingles faster. It also points to neighbours re-roofing: houses built around the same time, in the same weather, tend to reach the end of their roofs’ lives together.

Twenty years means different things for different materials. These are the published lifespans used across this site:

A 20-year-old three-tab roof is past its range, and a 20-year-old architectural roof has just entered it. A 20-year-old metal, tile or slate roof has not yet reached the low end of its range, so for those, condition matters far more than age. The roof lifespan guide has a roof age check and the cost per year of each material.

You have found a sign: repair or replace?

Two published tests are used on this site, and they point the same way. HomeGuide’s roof replacement guide says repair can make sense only when all three of these are true:

• less than 25 percent of the roof is damaged,
• the repair costs less than 30 percent of a new roof, and
• the roof is less than 20 years old.

HomeGuide’s roof repair guide turns that around. Replacement is the better call if the roof is more than 20 years old, the repair estimate is over $3,000, or the damage affects more than a quarter of the roof. Fixr frames it by what is left: repairs are worth it when localised damage sits on a roof with ten or more years of useful life remaining, while widespread wear, moss or missing shingles point to replacement.

The simplest way to weigh a quote is cost per year. A $3,000 repair that buys two more years costs $1,500 a year, while a $7,500 replacement that lasts 20 to 30 years costs $250 to $375 a year. Our roof repair cost guide works through that arithmetic, and the roof replacement cost calculator gives a range for a new roof on your house.

Get it inspected

A roof inspection costs $100 to $400, which is small against a repair or a replacement, and it replaces guesswork with a report you can compare quotes against. Ask the inspector three things: where any leak is coming from, how many years the roof has left, and whether the attic is properly ventilated, since poor ventilation is one of the causes of curling that a new roof would inherit.

Age also matters to your insurer. The Insurance Information Institute says roofs over 20 years old usually need to pass an inspection to be insured, and older roofs may be limited to actual cash value coverage, which pays less after a claim.

Sources used on this page

• IBHS FORTIFIED, 8 ways to know if you need a new roof, February 8, 2022, checked September 15, 2026. Leaks, curled, cracked and missing shingles, moss and algae, granule loss, rusted gutters and flashing, sagging roofs and exposed nails.
• Owens Corning, Do I need a new roof?, March 26, 2025, checked September 15, 2026. Curled and cupped shingles, bald spots, cracked shingles, the 20-year sign, neighbours re-roofing, dark streaks, moss and ladder safety.
• HomeGuide roof replacement cost guide, dated November 7, 2025. Lifespan by material, the three-part repair test and inspection cost.
• HomeGuide roof repair cost guide, dated February 9, 2026. The repair-versus-replace thresholds, leak repair costs by extent of damage, and sagging roof repair cost.
• Fixr roof replacement cost guide, last updated February 4, 2026. The ten-years-of-life-remaining repair guideline.
• Insurance Information Institute, how your roof influences your insurance. Inspections and coverage for roofs over 20 years old.

The cost-per-year comparison is our own arithmetic on those published figures. The checklist applies the thresholds above to what you tick and shows its reasoning; it is not a diagnosis. The methodology page explains how sources are used and how often pages are reviewed.