Does my roof need replacing?

A water stain on the ceiling is a good indicator that a roof covering is failing. Thermal imaging proves the leak is active. (Photo Contributed: Hugh Cairns)

Does my roof need replacing?

Q. Our roof is looking old. We are wondering when the best time to replace it is. Thank you, Leslie.

A. Hi Leslie, most homeowners replace their roof covering for one of two reasons; first, is because they want to, and the second is because they have to. Far too often homeowners find themselves in the position of having to replace their roof covering because they waited too long.

Determining a roof covering leak (failure) is fairly easy. You may see staining on your ceiling near drywall joints. As water travels it seeks the easiest way out. The weakest point in a drywall panelled ceiling is where sheets of drywall meet. To join the sheets, drywall mud is applied and sanded off to a smooth finish. When water penetrates through a drywall joint the stain starts as a circle shape and then progresses to a linear shape. Longer stains are an indicator of severity.

Your roof is expected to fulfill various functions for extended periods under extremely harsh and uncontrollable conditions. Changes in the performance of this roof is directly related to the initial design, the degradation mechanism(s) taking place, as well as the intensity, frequency and fluctuations of applied loads. Remaining service life isn’t always a function of age.

Estimating the general reliable service life of all types of roof coverings is pretty straight forward. Predicting exactly when a roof failure may take place is virtually impossible. Usually roof failure is noticed after it is well underway. The probability of failure of an aging roof system increases as the covering progressively ages.

Here are some tips to help you determine when a new roof covering may be in your future:

1. Roof age

Determining the age of your roof covering may be as easy as determining the age of your home. Another way is to look back at old receipts. The age of a roof covering is a commonly used tool to determine reliable service life prediction. It stands to reason that the probability of failure increases with age of the roof covering. Most asphalt shingle roof coverings in our area have reliable life expectancies of 25 to 30 years (or the published warrantied life).

2. Curling and buckling shingles

Curling and buckling shingles is another sign that the roof covering is aging.

3. Roof valleys

If you are experiencing accelerated deterioration in your roof valley’s it’s likely because of moisture retention. Valleys are one of the most important areas of your roof. Snow and rain flow through valleys and into gutters. If the valley is compromised, you could be susceptible to roof leaks.

4. Missing shingles

These are another sign your roof could be failing. When portions of your roof covering are missing, the chance of leaking increases dramatically.

5. Shingle granules in the gutters

Asphalt shingles have a protective coating of granules. Check in your gutters for granule buildup. Roof coverings tend to shed more granules toward the end of their reliable service life. You can also look at the covering from a distance for inconsistent or darker color patterning.


Don’t let cosmetic deterioration to be the sole determining factor. Just because something is old, it doesn’t mean that it’s not good. Just ask anyone over 50 years of age.