The useful life (UL) of an asset is the estimated length of time during which the asset is able to deliver a given level of service.
Alternate Definitions
The International Infrastructure Management Manual states that "useful life" may be expressed as either:
- The period over which a depreciable asset is expected to be used, or
- The number of production or similar units (i.e. intervals, cycles) that is expected to be obtained from the asset.
General Notes
The useful life of an asset is not necessarily equivalent to its physical life or economic life, a number of other factors may result in an assets useful life being reduced, including:
- Obsolescence
- Changes in community expectations
- Increased demands on capacity
- New legal requirments
Recommended Useful Lives
The useful life of most assets will depend on a wide range of environmental factors, but it is usually necessary to adopt a standard useful life for a range of asset types for asset management and accounting purposes. It would make life much easier if the state or federal governments published a list of default asset useful lives for Councils to use in the absence of better information, but with the notable exception of South Dakota in the United States, a quick internet search seems to suggest that this isn't a high priority for state governments around the world.
The table below is LGAMs attempt to compile a list of realistic asset useful lives. Hopefully after we have done all the hard work a state government or two will come on board and sanction them. Wouldn't be nice if you could tell your auditors that all of the useful lives you use are approved by the state government?
| Asset Type | Typical UL | Range |
|---|---|---|
| Asphalt Footpath | 30 years | |
| Asphalt Overlay | 20 years | 20-25 years |
| Brick Paved Footpath | 50 years | 30-80 years |
| Bridge | 80 years | 25-100 years |
| Building Envelope | 60 years | 45-75 years |
| Building Fire Services | 40 years | |
| Building Fitout | 30 years | 20-45 years |
| Building Mechanical Services | 30 years | 25-35 years |
| Bus Shelter | 20 years | |
| Concrete Floor | 100 years | |
| Concrete Footbridge | 50 years | |
| Concrete Footpath | 60 years | 20-80 years |
| Concrete Road Bridge | 85 years | 75-100 years |
| Culvert | 50-80 years | |
| Floor Coverings | 20 years | 5-40 years |
| Gravel Footpath | 12 years | 10-15 years |
| Gravel Resheet | 12 years | 5-20 years |
| Guardrails | 20 years | |
| Kerb & Channel | 60 years | 20-120 years |
| Lifts & Transport Services | 25 years | |
| Metal Park Bench | 20 years | |
| Main Double Iron Gate | 30 years | |
| Playground Equipment | 15 years | |
| Reinforced Concrete Stormwater Pipe | 100 years | 80-120 years |
| Retaining Wall | 25 years | |
| Road Formation | 150 years | 150 years-infinity |
| Road Pavement | 80 years | 20-120 years |
| Roof | 50 years | 15-90 years |
| Runway | 30 years | |
| Sewer Maintenance Hole | 80 years | |
| Sewer Pipe | 75 years | 65-80 years |
| Sprayed Seal | 15 years | 12-30 years |
| Steel Footbridge | 45 years | 40-50 years |
| Stormwater Pipe | 60 years | |
| Stormwater Pit | 90 years | 80-100 years |
| Street Lighting | 25 years | 20-50 years |
| Timber Footbridge | 30 years | 25-40 years |
| Traffic Signals | 25 years | 15-40 years |
| Weld Mesh Fencing | 30 years | 20-30 years |
Related Pages
- Building Useful Lives
- Council Asset Useful Life Tables
- Infrastructure Asset Useful Lives Report
- Lifecycle Cost Analysis
- Moorabool Shire Council Asset Service Life Spreadsheet
- Remaining Useful Life
- Residual Value
- Water Main Useful Lives
External Links & References
- Infrastructure Asset Useful Lives (LGA.SA)
- Boroondara City Council Asset Management Plan for Roads
- South Dakota Municipal Asset Useful Life Table
- Road Safety Engineering Risk Assessment Part 4: Treatment Life for Road Safety Measures (Austroads)
- Lifecycle Cost Guidelines for Sport and Recreation Facilities (Western Australian Department of Sport Recreation)
- Tweed Shire Council Drainage Assets Management Plan
