How Long Should Your Plumbing Last? A System-by-System Guide

One of the most useful things a homeowner can know is the expected lifespan of each plumbing system in their home — not because you can prevent the inevitable, but because you can plan for it. In Tucson, our hard water and high mineral content shorten certain lifespans below national averages. Here is what to expect.

Supply Pipes: The Delivery System

• →Copper: 50–70 years nationally, 40–60 years in Tucson (hard water and occasionally corrosive soil accelerate oxidation on exterior runs)
• →CPVC plastic: 50–75 years in normal conditions
• →PEX: 50+ years — the most durable modern supply material and highly resistant to scale
• →Galvanized steel: 20–50 years, but many Tucson homes with original galvanized are past this — scale narrows the interior diameter continuously

Drain, Waste, and Vent Pipes: The Removal System

• →PVC (plastic drain lines): 25–40 years under normal use
• →ABS plastic: 50–80 years
• →Cast iron: 75–100 years, though joint seals fail earlier
• →Clay sewer lines (common in older Tucson neighborhoods): 50–60 years, but root intrusion is a major failure mode in mature tree neighborhoods

Water Heaters: Your Hot Water Delivery System

• →Tank gas water heater: 8–12 years in Tucson (hard water impact)
• →Tank electric water heater: 10–15 years
• →Tankless gas: 15–20 years with annual maintenance and softened water
• →Tankless electric: 15–20 years

Fixtures and Valves

• →Toilet: The porcelain lasts indefinitely; the internal mechanism (fill valve, flapper, flush valve) needs replacement every 5–10 years
• →Angle stop valves: 8–10 years — one of the most commonly failed components in older Tucson homes
• →Faucets: Good quality faucets last 15–20+ years; cartridges and aerators need maintenance every 3–5 years
• →Pressure regulating valve (PRV): 10–15 years

The Tucson Adjustment

Subtract 15–25% from national average lifespans for any water-contacting component due to our mineral load. The exception is exterior copper in areas with corrosive desert soil — that can fail earlier. If your home is approaching or has passed these thresholds, a plumbing inspection gives you a real picture of what is left in the systems and what is worth proactive replacement.