ROI Property ToolsSearch

Repair or Replace Checker

Enter the item's age and the two prices you have been quoted. The tool shows which common rules of thumb point which way. Nothing is sent anywhere.

Installed price, from a quote if you have one.

For example a gas smell, carbon monoxide alarm, a cracked heat exchanger, or water near wiring.

Fill in the boxes and the result appears here.

What can make this wrong?

  • Age is only a guide. Typical life expectancies from the NAHB study (2007). Real lifespans depend on installation quality, maintenance, climate and use.
  • The rules of thumb are not research. The 50% rule and the $5,000 rule are widely repeated, but we found no published study behind them.
  • Running costs: a new unit may use less energy, and an old one may be cheap to run.
  • Parts availability, warranty and how well the item has been maintained.
  • Hidden damage or related work that a technician would find.
  • Your plans for the property, such as selling soon.
  • Safety overrides cost. If you ticked the safety box, ignore the sums.

Assumptions

  • The typical lifespan is a published average for a component in ordinary conditions, from a 2007 industry study.
  • The two prices are the ones you enter, usually from quotes. The tool does not check them.
  • The 50% rule and the $5,000 rule are rules of thumb. They are widely repeated, but we found no published study behind them.

Where this applies. Lifespans are national averages and do not depend on where you live, but your climate and the price of work do. Your own quotes capture that.

Sources and method

Each line in the result is labelled Sourced lifespan, Rule of thumb or Your input, so you can see which parts rest on a published figure and which do not.

Read the full reasoning in Should I repair or replace it? and how we work out costs. This tool is information only.