Roof Maintenance & Life Expectancy

Maintenance
All roofs should be inspected and maintained. The type of maintenance and frequency varies (i.e., asphalt shingles do not need maintenance).  Built-up roofing should be recoated every 4 to 5 years. The life of a roof can be significantly prolonged if maintenance is accomplished.  (The maintenance activity for the various types of roofing materials is included in Attachment “A”.)

Estimated Age
Estimating the age of a roof can sometimes be difficult.  On newer homes, the age of the roof is normally the age of the house.  Check for multiple layers, which is a good clue.  If the roof has: (a) several different materials; (b) the same material on different exposures; or (c) materials of different ages, each one of the differences should be evaluated separately.

Life Expectancy (Design Life)
The life expectancies of various roofs are included in Attachment “A”.  The exposure of a roof to weather (i.e., sunlight) will significantly decrease its life expectancy.  A south or west-facing roof very often is in a poorer condition than the north or east-facing surfaces on the same structure.  Other major factors in the life expectancy of the roof are slope, shade, color, etc.  A well-shaded, low-sloped wood roof on the north side of a property will very often gather moss, mildew, etc. and deteriorate more rapidly than one that is not.

Remaining Life
The remaining life of the roof is not necessarily determined by subtracting estimated age from life expectancy.  It is possible to have a two-year-old roof with a life expectancy of 20 years and have zero life remaining due to a product defect.  Many factors can affect this.  They include the manufacture, installation, wear, maintenance, etc.  The actual condition of the roof determines remaining life.