How long until tankless pays back on the North Shore?

With current Nicor Gas rates, energy savings of $100–$200/year are typical. Combined with the longer lifespan (20 vs. 10 years), total-cost-of-ownership favors tankless over a 15-year horizon — but the payback on the upfront premium alone is typically 6–10 years.

Does the gas line always need to be upsized for tankless?

Not always. If the existing ½-inch gas line is short and the appliance load elsewhere in the home is low, it may be adequate. Legendary assesses gas pressure at the water heater location before quoting — if upsizing is needed, it's in the flat-rate quote.

Plumbing · Compare

Tank vs. Tankless Water Heater: Side-by-Side Comparison

Name: Legendary Service
Address: 25741 N Hillview Ct, Mundelein, IL, 60060, US
Telephone: (847) 553-4041
Price range: $$

A storage tank water heater maintains a reservoir of hot water (40–80 gallons) at all times. A tankless unit heats water instantly when a tap opens. Both use natural gas in most North Shore homes. The difference: tankless eliminates standby heat loss; tank units cost less to install.

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50-gallon gas storage tank

Strengths

Lowest installed cost ($1,100–$1,800)
Simple installation — often direct replacement with no gas line work
Works well for households of 2–4 people with standard usage
Broad service availability throughout the North Shore
No minimum flow rate requirement

Trade-offs

Standby heat loss wastes 15–25% of energy keeping water hot 24/7
Runs out of hot water with simultaneous high demand
Typical lifespan 8–12 years
Takes up more floor space than a tankless unit

Condensing tankless gas

Strengths

UEF 0.90–0.96 — 20–35% more efficient than a standard tank
Unlimited hot water — no recovery wait
20+ year lifespan with maintenance
Wall-mounted, frees floor space
Nicor Gas rebate up to $150 available

Trade-offs

Higher installed cost ($2,500–$4,800) — often requires gas line upsizing
Requires annual descaling on North Shore hard water (Lake County 15–20 gpg)
Minimum flow rate (0.5 GPM) — won't fire at very low flow
Cold-water 'slug' at startup — a few seconds of lukewarm water at the tap
More complex service — fewer technicians are tankless-proficient

Typical installed ranges

North Shore cost bands

Option	Typical range	Notes
50-gallon high-efficiency tank (power vent, UEF 0.80+)	$1,100–$1,800	Includes installation and permit. Nicor rebate may apply.
Condensing tankless (installed with gas line work)	$2,500–$4,800	Range reflects whether gas line upsizing is required. Nicor rebate up to $150.
Hybrid heat-pump water heater (240V electric)	$1,800–$3,200	Requires 240V circuit. ComEd rebates may apply. Basement installation recommended.

What changes the price

Household size and peak hot water demand
Whether the existing gas line can support tankless BTU demand without upsizing
Nicor Gas rebate availability for qualifying units
North Shore hard water — tankless requires annual maintenance
Available installation space and existing venting type

FAQs

How long until tankless pays back on the North Shore?: With current Nicor Gas rates, energy savings of $100–$200/year are typical. Combined with the longer lifespan (20 vs. 10 years), total-cost-of-ownership favors tankless over a 15-year horizon — but the payback on the upfront premium alone is typically 6–10 years.
Does the gas line always need to be upsized for tankless?: Not always. If the existing ½-inch gas line is short and the appliance load elsewhere in the home is low, it may be adequate. Legendary assesses gas pressure at the water heater location before quoting — if upsizing is needed, it's in the flat-rate quote.

Editorial provenance

Content by Legendary Service editorial team

Updated: 2026-07-29

Methodology

Guidance compares the stated system factors, applicable utility program rules, and the conditions that must be confirmed in the home. Figures are planning ranges, not quotes; Legendary Service provides an upfront flat-rate price after diagnosis.

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