Repair or replace? The four-factor decision
Planning bands and replacement estimates by system
| System | Planning band | Replacement estimate |
|---|---|---|
| HVAC | 12–22 yrs (typical 17) | $8,000–$20,000 |
| Furnace | 14–25 yrs (typical 18) | $3,500–$9,000 |
| Roof | 18–30 yrs (typical 25) | $8,000–$25,000 |
| Water Heater | 8–15 yrs (typical 12) | $1,500–$4,000 |
| Electrical Panel | 25–50 yrs (typical 35) | $3,000–$12,000 |
| Plumbing | 40–80 yrs (typical 50) | $4,000–$15,000 |
| Windows | 18–40 yrs (typical 25) | $5,000–$20,000 |
| Siding | 22–50 yrs (typical 30) | $6,000–$20,000 |
| Foundation | 50–100 yrs (typical 75) | $5,000–$30,000 |
| Insulation | 30–60 yrs (typical 40) | $1,800–$6,000 |
| Garage Door | 15–30 yrs (typical 22) | $900–$4,000 |
| Deck | 12–30 yrs (typical 18) | $4,000–$25,000 |
How to read a lifespan number without over-reacting to it
A lifespan range sizes the risk window. On its own it is not a reason to replace a working system — weigh it alongside three other factors.
Age against the band
How far into its planning band is the system? Age sets the width of the risk window. On its own it never sets the decision — plenty of systems run well past the band, and some fail early.
Observed condition
What does it look like right now — corrosion, staining, cracking, rust, water? Visible deterioration is the strongest signal a homeowner can collect without a technician, and it can overturn a comfortable age reading.
Maintenance history
Is there a service record, or is this the first time anyone has looked? Documented service pushes realistic life toward the top of the band. No history pushes it toward the bottom and raises the odds of a compounding failure.
Active symptoms
Is it currently short-cycling, leaking, tripping, noisy, or failing to hold output? An active symptom is a present-tense fact and outranks every projection on this page. A safety symptom stops the cost conversation entirely.
What the guidance levels mean
- Monitor — No action beyond normal service. Re-check condition annually and keep the record.
- Plan and fund — Nothing is wrong today, but the replacement is close enough that it belongs in a funded reserve rather than a surprise.
- Prioritise a professional assessment — Two or more factors point the same way. Get an expert opinion before spending on a repair, and get a second quote on anything substantial.
- Act now — There is an active symptom or a safety concern. Address it independently of any lifespan arithmetic.
Sources & methodology
HomeScore planning bands (conservative). Life-used percentages come from the same conservative planning bands, then get weighed against your repair quote, the system's condition, and what it is actually doing.
- Compiled dataset range
- A range from HomeScore's compiled lifespan dataset, covering brand and material entries by system. It describes a product category rather than your specific unit. HomeScore compiled lifespan dataset, averaged as the mean of entry midpoints. Attribution is at dataset level: we do not publish a primary source citation for each individual value.
- Planning assumption
- A deliberately conservative band we use for budgeting a system that is already installed and already aging. It runs shorter than the compiled dataset range on purpose. HomeScore planning bands (worst / typical / best) with a separate climate factor, held apart from cost so regional pricing never warps the years.
- What you told us
- Values you entered — install year, age, repair quote, condition, maintenance history, symptoms. We never overwrite these or guess them for you. Your inputs in this session, held in your browser only.
- Calculated guidance
- Arithmetic on the two above: years used, years remaining, cost ratios, and the resulting guidance. It is a planning output, not a forecast of failure. Deterministic calculation shown on this page — no model, no prediction.
Dataset v2026.1 · published 2026-04-22 · lifespan-method:v1. Ranges are planning inputs, not guarantees of service life, and no figure here predicts that a specific system will fail in a specific year. Citable extract (CC BY 4.0).