A concrete foundation might last for a century or more, the roof covering might keep out the rain for twenty years, and carpets might have to be replaced every five years. Even with regular maintenance, buildings contribute less value as they age. This loss of value with age is called physical depreciation. Buildings don t necessarily decrease in value at a steady rate. Good maintenance and periodic upgrades can extend the economic life of a building.
Buildings go out of style and become obsolete, regardless of how well they have been cared for.
Even if the building is in good shape, the floor plan may be awkward and the fixtures outdated. Some buildings suffer from botched remodeling jobs. Other buildings are just badly designed to begin with. This loss of value due to diminished functional utility is called functional depreciation. A professional building inspector can do a thorough investigation that will reveal deferred maintenance, outdated features and bad construction.