What a tankless water heater costs on the North Shore.
Tankless water heater installation on Chicago's North Shore typically runs $3,500-$6,500 installed. The equipment is only part of it. Converting from a conventional tank usually brings a gas line upsize, new stainless or PVC venting out a sidewall, and a condensate drain, and those three items are why a tankless conversion prices well above a like-for-like tank replacement.
Published 2026-08-31 · Last reviewed 2026-08-31 · Typical installed project totals for the Chicago North Shore, not quotes.
Cost by home size
Square footage drives capacity and capacity drives price. These are the same size adjustments the instant estimate calculator uses, so the two never disagree.
| Home size | Typical installed |
|---|---|
| Smaller homes (under 1,500 sq ft) | $3,000-$5,700 |
| Typical homes (1,500-2,500 sq ft) | $3,500-$6,500 |
| Larger homes (2,500-4,000+ sq ft) | $3,900-$8,600 |
What the range covers
- Tankless unit, mounting, and the water connections with isolation and service valves
- Venting for the unit's category, run to a sidewall termination
- Gas line work at the appliance, and the electrical connection the ignition and controls require
- Condensate drain and neutralizer on a condensing unit
- Removal and haul-away of the old tank, plus commissioning and temperature setup
- Gas line upsizing back toward the meter where the existing line cannot carry the load
- Water softening or whole-house filtration, which is a separate trade
- A recirculation loop where the house does not already have one
- Chimney lining for a water heater left orphaned by a different appliance change
What actually moves the number
- The gas line is the usual surprise
- This is the item that turns a tidy quote into a large one and it catches most conversions. A conventional tank might draw around 40,000 BTU. A whole-house tankless can want 150,000 to 199,000, all of it at once. The existing branch is frequently too small to deliver that, and the fix is running a larger line back toward the meter, sometimes across a finished basement. Any quote that has not physically traced the gas line has not priced the job.
- Venting, and getting off the chimney
- A tankless unit does not vent up a masonry chimney. It vents horizontally out a sidewall in stainless or, on a condensing unit, in PVC. That means a new penetration in a location that satisfies clearance from windows, doors and the property line, which on a tight North Shore lot is a genuine constraint. It also means that if the old tank shared a flue with a furnace, whatever is left on that chimney has to be reassessed.
- Incoming water temperature in a Chicago winter
- A tankless unit is rated by how far it can raise the water temperature at a given flow. Incoming municipal water here is cold in February, which lowers deliverable flow exactly when demand is highest. Sizing has to be done against winter incoming temperature and simultaneous fixture use, not against a summer rating on a brochure. An undersized unit produces the complaint everyone associates with tankless, which is a shower that goes cool when someone else opens a tap.
- Water hardness and what maintenance actually looks like
- Chicagoland water leaves scale, and a tankless heat exchanger has narrow passages that scale closes up. These units want descaling roughly annually to hold their rated output and their warranty. That is an ongoing cost of ownership a tank does not have, and it should be part of the decision rather than a surprise in year three. Homes with a softener already installed have an easier time of it.
- Recirculation and the wait at the tap
- A tankless unit does not store hot water, so a long run to a far bathroom means a longer wait than a tank at the same distance. Adding a recirculation loop or a unit with a built-in recirculation feature fixes it and adds cost. In a large older house with a bathroom at the far end, this is worth pricing in at the start.
When a conventional tank is the better buy
A tankless unit is the right call when the household genuinely runs out of hot water, when the mechanical space is worth reclaiming, or when the existing gas line and a sidewall vent location are already workable so the conversion cost stays contained. A conventional tank is the better buy more often than the marketing suggests: when the gas line would need a long upsize, when there is no acceptable sidewall termination, when the household's usage is modest and steady, or when the water heater simply failed and the priority is hot water this week at the lowest defensible cost. The efficiency gain is real but it is a water heater, and a payback calculated on top of a large gas line and venting bill is a long one.
Tankless water heater installation cost, which is most of the price
With a tankless unit the installation genuinely is the cost, more so than with any other equipment on this site, which is why this phrasing of the question deserves a straight answer rather than a redirect to the equipment price. A tankless conversion is three trades: the unit, a gas line usually upsized to deliver several times the BTU of the tank it replaces, and a new sidewall vent penetration with a condensate drain. In a North Shore house where the water heater sits in the middle of a basement, far from an exterior wall and on a gas line already carrying a furnace and a range, those three things cost more than the appliance does. In a house already plumbed and vented for tankless, replacing one is close to a swap and the number falls sharply. Ask any quote to separate the unit from the gas and venting work, because that split is the entire explanation for why two bids differ.
Nicor Gas has historically offered a modest rebate on qualifying high-efficiency tankless units, and the amount and eligibility move more often than the furnace and boiler programs do, so it is worth confirming what is current at the time of the quote rather than budgeting from a figure found online. Homes served by North Shore Gas fall under a different program. The federal 25C credit ended for equipment placed in service after December 31, 2025.
Current ComEd and Nicor rebatesMethodology
This range is the typical installed project total for tankless water heater installation across Chicago's North Shore - Evanston, Wilmette, Winnetka, Kenilworth, Glencoe, Highland Park, Lake Forest, Northbrook, Glenview and the surrounding communities. It reads from the same figures as the instant estimate calculator and the main cost reference, so there is one set of numbers on this site rather than three. Ranges are reviewed as equipment and utility program pricing move, and the last-reviewed date above is accurate rather than automatic.
Tankless Water Heater Installation cost questions
$3,500-$6,500 installed on Chicago's North Shore. A conversion from a conventional tank that needs a gas line upsize and new sidewall venting sits at the top of that range; a straightforward replacement of an existing tankless unit sits at the bottom.
Because a tank replacement is largely a swap and a tankless conversion is three trades. The unit itself is more expensive, and then there is usually gas line work to deliver several times the BTU, a new vent penetration through a sidewall, and a condensate drain. Strip those away - as in a house already set up for tankless - and the gap narrows considerably.
You will not run out, but you can outrun it. A tankless unit delivers a continuous flow rate, not an unlimited one, and that rate falls when incoming water is cold. Two showers and a dishwasher at once in February is the condition that has to be sized for. Sized correctly it does what people expect; sized off a summer rating it disappoints.
It is the main ongoing maintenance item here. Scale builds in the heat exchanger's narrow passages and reduces output, and manufacturers expect roughly annual descaling to keep the warranty intact. Isolation valves installed at the same time as the unit make that a routine service rather than a project, and a house with a water softener has an easier time of it.
Longer than a tank when it is maintained, which is much of the argument for one. That advantage is conditional on the descaling actually happening. A neglected unit in hard water does not reach its expected life, and at that point the conversion cost was spent for nothing.
$3,500-$6,500 installed on Chicago's North Shore, and unlike most equipment it is the installation rather than the unit that decides where you land in that range. A conversion needing a gas line upsize and a new sidewall vent is at the top. Replacing an existing tankless unit in a house already set up for one is at the bottom. Ask for the unit price and the gas and venting work as separate lines.
“Tankless Water Heater Cost on the North Shore (2026): $3,500-$6,500 Installed,” North Shore HVAC Replacement, last reviewed 2026-08-31. https://northshorehvacreplacement.com/costs/tankless-water-heater/
Other system costs
The instant estimate calculator gives you a range for your house in about a minute, and it shows the number before it asks for your contact information. $3,500-$6,500 is the planning range; your house has one number inside it.