The tank (or tankless unit) that heats the home's water. A conventional storage tank typically lasts 8–12 years; past about 10 it's on borrowed time, and past about 12 a failure — and a wet floor — can happen any day. Inside a tank, a sacrificial anode rod corrodes in place of the steel tank wall; in hard-water areas it can be used up in 3–5 years, and once it's gone the tank itself starts to rust, which is what eventually ends the unit's life.
$1,200–2,500 to replace a tank ($3,000+ for tankless)Address soonPlumbingHeating
Why it matters
It's not dramatic, but it's a near-certain near-term cost and an easy negotiation chip — and a leaking tank can damage finishes below it. The key is simply knowing the age, which is printed on the label and which most buyers never check. (Note: in much of Ontario, water heaters are often rented, not owned — worth confirming, since a rental contract transfers with the home.)
How to spot it
Read the manufacture date on the rating label (if there's no plain date, the serial number usually encodes the year and week). Watch for rust at the base, corrosion at the fittings, or pooling. Note whether it's a tank or tankless, gas or electric, owned or rented, and whether the temperature/pressure (T&P) relief valve has a proper drain pipe.
What it costs
Roughly $1,200–2,500 to replace a tank; $3,000+ for a tankless unit (which lasts longer but costs more up front).
What to do
Address soon if it's near end of life — get the age, budget a replacement, ask the agent when it was last replaced, and confirm whether it's owned or on a rental contract.
Education and triage, not a home inspection. Casaroo reads the age off your label photo and estimates remaining life — a licensed plumber or gas technician confirms condition.
Common questions
What is Water heater age & end of life?
The tank (or tankless unit) that heats the home's water. A conventional storage tank typically lasts 8–12 years; past about 10 it's on borrowed time, and past about 12 a failure — and a wet floor — can happen any day. Inside a tank, a sacrificial anode rod corrodes in place of the steel tank wall; in hard-water areas it can be used up in 3–5 years, and once it's gone the tank itself starts to rust, which is what eventually ends the unit's life.
Why does it matter for home buyers?
It's not dramatic, but it's a near-certain near-term cost and an easy negotiation chip — and a leaking tank can damage finishes below it. The key is simply knowing the age, which is printed on the label and which most buyers never check. (Note: in much of Ontario, water heaters are often rented, not owned — worth confirming, since a rental contract transfers with the home.)
How can I spot it?
Read the manufacture date on the rating label (if there's no plain date, the serial number usually encodes the year and week). Watch for rust at the base, corrosion at the fittings, or pooling. Note whether it's a tank or tankless, gas or electric, owned or rented, and whether the temperature/pressure (T&P) relief valve has a proper drain pipe.
How much does it cost to fix?
Roughly $1,200–2,500 to replace a tank; $3,000+ for a tankless unit (which lasts longer but costs more up front).
Lifespans vary with water hardness and maintenance; a licensed plumber/gas technician confirms condition. Casaroo flags, it does not inspect.
Last reviewed 2026-06-27.
Casaroo reviews each guide against current pricing, code, and insurer practice. Cost ranges are 2026
estimates that vary by region, size, and access — confirm specifics with a licensed professional.