How long do home systems last?

How long each part lasts

InterNACHI is a home inspectors' association. Its chart assumes regular maintenance and normal wear, leaves out extreme weather and neglect, and calls its figures guidelines, not guarantees. The same is true of every number here: a real house lands somewhere around them.

What shortens a system's life in Orange County?

• Hard water. InterNACHI notes that the mineral content of water can shorten a water heater's life. Much of Orange County's water is hard (by provider in our hard water guide), so a tank flush or tankless descale is the maintenance InterNACHI's figures assume.
• Sun and heat. The same chart says UV light shortens life expectancy and that hot climates drastically reduce asphalt shingle life. Check yours from the ground once a year.
• Salt air. A FEMA technical bulletin says salt spray is heaviest at the shoreline, drops off sharply over the first 300 to 3,000 feet, and has sped up corrosion of metal as far as 5 to 10 miles inland. An AC condenser is outdoor metal sitting in that air. Our maintenance checklist covers rinsing and the rest of the coastal routine.
• Aging hoses. A study by the Institute for Business and Home Safety found that washing machine hose failures climb sharply after five years, and that failed hoses averaged 8.7 years old. Whirlpool says to replace the fill hoses every five years.

When should I start planning a replacement?

ENERGY STAR suggests thinking about it once a water heater, heat pump or air conditioner is more than 10 years old, or a furnace is more than 15, so a failure does not force a rushed choice. The cost guides linked in the table cover repair versus replace and what each job costs. If the cost is out of reach, our home repair help guide lists city, county and utility programs that can help.

How do I find out how old mine is?

Start with the label. To date a water heater, ENERGY STAR says to find its brand name and serial number. A smoke alarm has its manufacture date printed on it, and the U.S. Fire Administration counts its 10 years from that date. For anything without a label, the year the house was built is a starting point, and our guide to how old Orange County homes are shows what that usually means.

Sources checked October 9, 2026. General information, not an inspection. A licensed inspector or contractor can tell you where your own systems stand.