Localized for 1,000+ U.S. cities — adjusted for local labor, climate & permits
City comparison

Tankless Water Heater Installation cost: Brentwood vs Makakilo / Kapolei / Honokai Hale (2026)

Brentwood runs 9% lower than Makakilo / Kapolei / Honokai Hale for tankless water heater installation — expect around $4,100 in Brentwood against $4,450 in Makakilo / Kapolei / Honokai Hale, a difference of about $350.

Brentwood TN

Lower cost
$2,550 $5,600

Typically around $4,100

Makakilo / Kapolei / Honokai Hale HI

$2,800 $6,050

Typically around $4,450

The $350 (9%) premium on tankless water heater installation in Makakilo / Kapolei / Honokai Hale versus Brentwood comes down mostly to local labor rates.
Side by side

Brentwood vs Makakilo / Kapolei / Honokai Hale: full breakdown

FactorBrentwoodMakakilo / Kapolei / Honokai Hale
Typical 2026 cost$4,100$4,450
Estimated range$2,550–$5,600$2,800–$6,050
Labor index (vs US)×0.97×1.07
Climate zoneMixedHot
Climate factor×1×0.98
Local permit$150$175
Labor share$2,250$2,450
Materials/equipment$1,850$2,000

Localized 2026 planning estimates — not quotes. Each city adjusts the national tankless water heater installation range for local labor, climate and permits.

The verdict

Is the gap worth worrying about?

A 9% spread (roughly $350) is significant enough to plan around, but not fixed — off-peak timing and sharper bidding in Makakilo / Kapolei / Honokai Hale typically recover some of it.

By type

Tankless water heater installation by type: Brentwood vs Makakilo / Kapolei / Honokai Hale

Below, each tankless water heater installation option is priced independently for both cities, with identical local labor, climate and permit logic applied — so the comparison holds up.

TypeBrentwoodMakakilo / Kapolei / Honokai Hale
Gas tankless$3,050$6,450$3,350$7,000
Electric tankless$1,800$3,250$1,950$3,550

Localized 2026 planning estimates — not quotes. Each city adjusts the national tankless water heater installation range for local labor, climate and permits.

By size

Tankless water heater installation by flow rate (GPM): Brentwood vs Makakilo / Kapolei / Honokai Hale

Tankless units are sized by flow rate — gallons per minute (GPM) — rather than tank size. Add up the fixtures you'd run at once: a shower is ~2 GPM, so a larger household needs a higher-GPM unit (or two).

SizeBrentwoodMakakilo / Kapolei / Honokai Hale
5–7 GPM (1–2 people, 1 bath)$2,300$4,200$2,500$4,600
7–9 GPM (2–3 people, 2 baths)$2,650$4,900$2,900$5,300
9–11 GPM (3–4 people, 2–3 baths)$3,050$5,400$3,350$5,850
11+ GPM (5+ people / whole-home)$3,550$5,850$3,850$6,350

Localized 2026 planning estimates — not quotes. Each city adjusts the national tankless water heater installation range for local labor, climate and permits.

Local labor reality

What water heaters pros earn in each metro

About 55% of a tankless water heater installation bill goes to labor, so wage differences between these two metros matter more than almost anything else. These are real, government-sourced (BLS OEWS) installer wages, not estimates.

Brentwood, TN
$29.4/hr

Nashville-Davidson--Murfreesboro--Franklin metro · about 6% below the US average installer wage.

Makakilo / Kapolei / Honokai Hale, HI
Modeled from state data

No BLS metro wage series for Makakilo / Kapolei / Honokai Hale; we use Hawaii regional price parity instead.

Source: U.S. Bureau of Labor Statistics, OEWS metro wages for HVAC installers (used as a trade-labor index).

Best time to buy

Cheapest time for tankless water heater installation in either city

The failure pattern is predictable: cold water plus heavy winter demand kills aging tanks, and everyone needing emergency service pushes prices up together. Getting ahead of it in a quiet month sidesteps the rush.

Best window
Spring and early fall
Avoid
Deep winter (failure season)
Off-peak savings
5–10%
Editors' roundtable

Tank or tankless — and what should you budget?

Before the brand or the size, the biggest decision in a water heater budget is the format. Here's how our editors think through it.

The simple-swap case

If your current tank suits your household and the budget is tight, a like-for-like tank replacement is the cheapest, fastest job — no gas-line or panel upgrades, done in a morning.

The heat-pump case

A heat-pump (hybrid) water heater costs the most upfront but slashes operating cost and earns the strongest utility rebates where offered — the long-run winner where the install location suits it.

The tankless case

Tankless costs more upfront and may need a gas-line or electrical upgrade, but it lasts longer, never runs out of hot water and trims standby energy loss — strongest for larger households planning to stay put.

Our take

The right format depends on how long you're staying and what you're optimizing for: upfront cost favors tank, convenience favors tankless, and long-run savings favor heat-pump.

FAQ

Brentwood vs Makakilo / Kapolei / Honokai Hale

Is tankless water heater installation cheaper in Brentwood or Makakilo / Kapolei / Honokai Hale?

Yes — Makakilo / Kapolei / Honokai Hale costs more. Expect around $4,450 for tankless water heater installation there against $4,100 in Brentwood, about $350 (9%) apart in 2026.

Why does tankless water heater installation cost more in Makakilo / Kapolei / Honokai Hale than Brentwood?

Makakilo / Kapolei / Honokai Hale's higher labor index (1.07 vs 0.97 in Brentwood) is the biggest factor, with the hot/mixed climate split and permit fee differences playing a smaller role.

How much is tankless water heater installation in Brentwood, TN?

Expect to pay $2,550 to $5,600 for tankless water heater installation in Brentwood in 2026, averaging around $4,100.

When is the cheapest time to buy tankless water heater installation — and does it differ by city?

The best window is the same in both Brentwood and Makakilo / Kapolei / Honokai Hale: Spring and early fall, when demand drops and installers discount to keep crews busy — typically 5–10% off peak pricing. The most expensive time anywhere is an emergency replacement during deep winter (failure season).

Should I choose where to live based on tankless water heater installation cost?

Not really — the $350 gap is one-time, and smart timing and tighter quotes in Makakilo / Kapolei / Honokai Hale can shrink it. Factors that compound over time, like energy prices and home condition, deserve more weight than a single upfront difference.

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Updated June 2026 · By Serhat Özçelik