Useful Life (UL)

Useful life is the total number of years a reserve component is expected to serve its purpose when it is installed and maintained properly.

A composition shingle roof might have a useful life of 20 to 25 years. Asphalt paving, an elevator modernization and exterior paint each have their own typical span.

Useful life is an estimate, not a warranty. It depends on the quality of the materials, how the item was installed, the local climate, how heavily it is used and how well it is maintained. The same roof lasts longer in a mild climate than on an exposed coastline.

Preparers set useful life from manufacturer data, published cost guides, the association's own history and their experience with similar properties. A good study records where the figure came from.

Useful life works together with remaining useful life. Useful life is the whole span. Remaining useful life is what is left. The difference between them is the effective age, which decides how much of the component's cost should already be in reserves.

Source: this definition follows the National Reserve Study Standards, published by Community Associations Institute (CAI), explained in our own words. State law can define the term differently for its own purposes.