AVERAGE LIFESPAN OF A ROOF
The life expectancy of a roof varies between different roof materials. Here’s the averages:
But average lifespan estimates are based on “average” conditions. Many factors contribute to a longer or shorter life of the roof; so a particular roof’s life can vary—sometimes significantly—from the average. Here’s a list of conditions that affect roof longevity:
- Color of roof – A dark roof absorbs more heat, which shortens the lifespan.
- Angle of roof slope – Higher pitch roofs tend to last longer.
- Orientation of roof surface – A roof slope facing south will get more sunlight, and have a shorter life.
- Multiple-layer roof – A roof installed over an existing roof will have a shorter life.
- Quality of roof material – “Economy” roof materials have a shorter life.
- Installation – Sloppy or improper installation shortens roof life.
- Attic ventilation – An unventilated or poorly ventilated attic reduces roof lifespan.
- Trees near roof – Tree branches rubbing on a roof or the acidity from the accumulation of leaf debris on a roof shortens its life.
- Harsh climate – Severe weather, both harsh winters and hot summers, along with big temperature swings within a 24-hour period, also shorten lifespan because of the expansion and contraction of roof materials.