How To Look At A House

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How accurate are the average life expectancy ratings of home components? Are they actually useful?

Sunday, June 24, 2018

According to the Social Security Administration’s actuarial table, the typical 65-year old American can expect to live to the age of 83. Some will depart this world sooner, and about 10% will live to 95. Old air conditioners, along with the other replaceable components of your home, are much like that. It’s easy to find out the average lifespan, but pinpointing the month when the service van will pull up to take away your old air conditioner and cart in a new one is just not possible.

    While not an exact predictor, average lifespan is still a valuable piece of information. For example, let’s say you are buying an 20-year-old home with its original shingle roof, air conditioner, and water heater. If you look at the listing of expected lifespans at our article What is the average life expectancy of the components of a house?, you’ll see that all three of them would be either right at, or past, their average life expectancy.

   And while it is possible that one of those three costly replacement items may have a surprisingly long life, it’s also true that the likelihood of one of them requiring replacement soon is almost 100%.

   So average lifespan charts help you to estimate what big-ticket replacement expenses you can reasonably expect in the first years after you purchase a home. Condo association managers use the charts also, to prepare detailed budgets for expected replacement cycles for each building component. This forms the basis for part of the monthly assessments--setting aside an amount each month for the estimated future date of a roof replacement for the entire complex, for example. You can do the same thing on a smaller scale, as a buffer against the inevitable future expenses of owning a home.

    We have based the lifespan estimates on three sources:

  1. The National Association of Home Builders (NAHB) “Study of Life Expectancy of Home Components,” compiled in 2006.
  2. The International Association of Certified Home Inspectors (InterNACHI) “Standard Estimated Lifespan Expectancy for Homes.”
  3. Our own experience in inspecting over 7,500 homes in both South and North Florida.

    The spread in years of the average lifespan ratings is due to multiple factors, which include things like quality of the manufactured product, weather exposure, maintenance, and level of usage.

   Visit our LIFE EXPECTANCY page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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