Table of Contents
  1. Roofing
  2. HVAC Systems
  3. Water Heater
  4. Plumbing
  5. Electrical
  6. Appliances
  7. Exterior
  8. Windows and Doors
  9. Interior
  10. The Most Important Number

How Long Does Everything in Your Home Last?

One of the most useful things you can know as a homeowner is when things are going to wear out. Not because you can stop it from happening, but because anticipating it puts you in a planning posture instead of an emergency posture. An HVAC system that dies unexpectedly in August costs the same to replace as one you knew was coming — but the emergency replacement happens faster, with less time to get competitive quotes, and usually at a premium.

What follows is a comprehensive guide to the expected lifespans of major home systems and components, along with the warning signs that indicate you're approaching the end of the line.

Roofing

Warning signs: curling or cupping shingles, granule loss (check your gutters — excessive granules mean the shingles are shedding protective coating), missing shingles, dark staining, daylight visible in the attic. Roof replacement is one of the largest homeowner expenses: $8,000–$25,000+ depending on materials, size, and complexity.

HVAC Systems

Warning signs: uneven heating or cooling, unusual noises (grinding, banging, squealing), rising energy bills without explanation, frequent cycling, visible rust or corrosion. Annual professional maintenance extends life significantly. A furnace that's been serviced every year will last longer than one that hasn't. Replacement costs: $4,000–$15,000 for a full system replacement.

Water Heater

Warning signs: rust-colored water, rumbling or popping sounds during heating (sediment buildup), water around the base of the unit, inconsistent hot water supply, visible corrosion on the tank or connections. Annual flushing extends life in hard-water areas. Replacement: $900–$3,000 for tank, $1,500–$4,000 for tankless installed.

Plumbing

The main thing to know about plumbing is that the supply lines to individual fixtures are the most failure-prone and most ignored component. Those braided stainless hoses under your sink and behind your toilet? Replace them every 10 years whether they look fine or not. The cost is under $20 per line. A burst supply line on a second floor can cause tens of thousands in damage.

Electrical

Warning signs for electrical issues: frequently tripping breakers, flickering lights, discoloration or warm outlets, burning smell, breakers that won't reset. If your home has a Federal Pacific Stab-Lok or Zinsco electrical panel, have it evaluated by an electrician — these brands have documented reliability and safety concerns and many electricians recommend proactive replacement.

Appliances

Appliances are the most unpredictable category — some fail at 8 years, some last 20. Extended warranties on appliances over $1,000 are worth considering, particularly for refrigerators and washing machines, which tend to have expensive repair parts.

Exterior

Windows and Doors

Interior

The Most Important Number

If you can only track one number, track the age of your water heater. It's the system most likely to fail catastrophically (flooding) without obvious warning, it has the clearest lifespan (8–12 years for a tank unit), and replacement is straightforward. If you don't know how old your water heater is, look at the serial number on the unit — most manufacturers encode the manufacture date in the first few characters, and manufacturer websites provide decoding guides.

Beyond the water heater, build a simple spreadsheet of your major systems, their approximate age, and their expected lifespan. KotiCare does this automatically from your inspection report — tracking every system’s age and condition, surfacing reminders before failures occur, and connecting you with vetted contractors when work is needed. Whether you use a tool like KotiCare or build a manual tracker, this document alone will transform your home maintenance from reactive to proactive.

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