How Much Does a New Furnace Cost in Glenview? A 2026 Replacement Guide

Replacing a furnace in the Glenview area runs roughly $3,800 to $12,000 installed, and where you land in that range depends far more on which efficiency tier you choose than on which brand you buy. But two things changed for 2026 that most cost guides still have wrong, and one of them costs Glenview homeowners money in a way nobody warns them about.

This guide covers what the equipment actually costs, what drives the spread, the permit rule that quietly turns an efficiency upgrade into a bigger project, what happened to the federal tax credit, and which rebates are still worth claiming. If your furnace is still running and you're deciding whether to fix it instead, start with our furnace troubleshooting and repair cost guide — the repair-versus-replace math lives there.

1. The short answer: what it costs

National installed ranges for a gas furnace replacement in 2026, by efficiency tier:

AFUE stands for Annual Fuel Utilization Efficiency — the percentage of the fuel you buy that becomes heat in your house rather than exhaust out the flue. An 80% AFUE furnace sends one dollar in five up the chimney. A 96% unit sends one in twenty-five.

Chicago-area labor sits in the upper half of these ranges, and North Shore pricing runs above Chicago proper. A quote at the top of a tier isn't automatically padding — but it should come with a reason you can point at.

2. What actually drives your price

Efficiency tier — the biggest single lever

Moving from 80% to 96% AFUE roughly doubles the installed cost. That gap is not mostly the equipment; it's what the equipment requires, which the next section covers.

Size, in BTU

Furnace capacity runs from about 40,000 BTU for homes up to 1,200 square feet to 90,000–120,000 BTU for homes in the 2,500–3,000+ square foot range. Equipment-only cost moves from roughly $700–$2,300 at the small end to $1,600–$6,200 at the large end. Much of the North Shore's housing stock sits at the upper end of that spread.

Venting

This is the line item that surprises people. A conventional 80% furnace vents hot exhaust through an existing metal flue, often shared with your water heater. A condensing high-efficiency furnace extracts so much heat that its exhaust is cool and wet, which metal flues cannot handle — so it vents through new PVC piping, usually out a sidewall, and it needs a condensate drain.

That means a high-efficiency conversion is not a swap. It's new pipe routed through your house, a new exterior penetration, a drain line, and frequently a re-line or reconfiguration of the flue your water heater was sharing. It also has consequences at the permit desk — see section 3.

Ductwork

Modifications or repairs run roughly $300–$1,500. Full replacement runs $1,400–$5,600 and up. Older Glenview and North Shore homes with retrofitted or undersized ductwork are considerably more likely to need this, and a contractor who notices it is doing you a favor, not upselling you.

Gas line work

Roughly $15–$50 per linear foot, or $350–$2,000 total if a new run or resize is needed. More common when equipment is relocated or capacity changes materially.

Removal and disposal

Typically $150–$400. Frequently bundled, sometimes not. Worth confirming which.

3. The Glenview permit trap on efficiency upgrades

Here is the part no national cost guide will tell you, and it changes how you should think about the efficiency decision.

Now connect that to section 2. A high-efficiency condensing furnace requires different venting. So in Glenview:

• Like-for-like 80% replacement → same type, same venting → generally no permit.
• Upgrading 80% to 96% → venting necessarily changes → permit required.

The efficiency upgrade and the permit are the same decision. You cannot take one without the other, and a contractor quoting a high-efficiency conversion without a permit line is either absorbing it or skipping it.

Why you want the permit anyway

It reads like friction. It's actually the most useful consumer protection available to you, because of what the Village checks before issuing one: the contractor's license, bond, and insurance.

That gives you a free, third-party verification of the person about to spend a day inside your house doing gas and venting work — the exact category where unlicensed work turns into carbon monoxide problems. You don't have to evaluate their paperwork. The Village does it as a condition of the permit.

Which produces a genuinely useful test: a contractor reluctant to pull a permit may be reluctant because their paperwork won't survive the check. That reluctance is information. Treat it as such, before a deposit changes hands.

Mechanical work of this kind is eligible for same-day review in Glenview, so the permit is not a schedule problem. Applications go through the Village's online permitting portal or in person at the Development Center, 2500 East Lake Avenue.

4. What changed in 2026: the federal credit is gone

This matters beyond the $600 itself, because it quietly changed the math on efficiency upgrades. Through 2025, a homeowner weighing 80% against 96% could count a federal credit plus a utility rebate against the price gap. In 2026 the federal half of that is gone, and the gap between tiers didn't shrink to compensate.

The practical effect: high efficiency has to justify itself on fuel savings and comfort alone this year. For a large, leaky, older North Shore home with a long heating season, it often still does. For a smaller or well-insulated house, the payback period stretched out noticeably compared to last year.

Tax situations vary, and this is general information rather than tax advice — confirm your own position with a tax professional before counting on any credit.

5. Rebates that still exist

Utility rebates were not affected by the federal expiration. For the 2026 program year, Nicor Gas offers residential rebates on qualifying equipment:

Two details that cause people to lose the money:

1. Equipment must be installed between January 1 and December 31, 2026 to qualify under the current program year.
2. You must apply within 90 days of installation. This is the one that gets missed — the furnace goes in during a January cold snap, the paperwork goes in a drawer, and by the time anyone thinks about it in the spring the window has closed.

Applications are submitted through Nicor's online rebate portal, with paper applications available by phone. Some contractors handle the filing for you; most do not unless asked. Ask.

For the full picture — ComEd's heat pump discounts, what neither utility covers, and income-qualified assistance — see our guide to HVAC rebates in Glenview.

Note the thresholds, because they interact with the tier table in section 1: the rebate starts at 95% AFUE. A 90–94% furnace sits in an awkward spot — it costs meaningfully more than an 80% unit, triggers the venting change and therefore the permit, and still earns no Nicor rebate. If you're crossing into condensing territory at all, the case for going to 95% or 97% is stronger than the case for stopping at 92%.

6. The 2028 rule — should you wait?

You may hear that gas furnaces are being banned. They are not. Here is what is actually happening.

The Department of Energy finalized a standard requiring 95% AFUE for residential non-weatherized gas furnaces. A federal appeals court upheld it in a 2–1 decision on November 4, 2025. The compliance date is December 18, 2028, after which manufacturers must stop producing non-condensing furnaces.

Three things follow that are worth being precise about:

• It applies to manufacture, not installation. There is no contractor sell-through deadline and no installation ban. Existing 80% stock can still be installed after the date.
• It is more than two years away. A furnace failing in 2026 is not a reason to wait for anything.
• It does not make your current furnace illegal. Nothing requires you to replace working equipment.

For context on the cost debate the rule generated: the Appliance Standards Awareness Project projects average lifetime household savings of about $350, while a dissenting judge noted condensing furnace installation running roughly $1,345 against $801 for non-condensing. Both numbers can be true; they measure different things over different horizons. The honest summary is that the efficiency premium is real and the payback is slow in a moderate house.

If a salesperson uses 2028 as urgency — buy now before they're banned — that's a pressure tactic, not a fact.

7. Sizing: the most expensive mistake

The single most common error in residential furnace replacement is installing a unit that's too big, and it is usually made by defaulting to whatever size came out.

That default is wrong more often than it's right, because the old unit may itself have been oversized, and because the house has probably changed since — new windows, added insulation, a finished basement, an addition. A proper Manual J load calculation measures what the house actually needs: square footage, insulation levels, window area and orientation, air leakage, and local design temperature.

Why oversizing hurts

• Short cycling. An oversized furnace satisfies the thermostat fast, shuts off, and restarts. Ignition is the hardest moment in the equipment's life, and more cycles means faster wear.
• Uneven temperatures. Short runs never move enough air to distribute heat, so far rooms stay cold while the thermostat reads satisfied.
• Worse humidity and comfort, and often more noise from oversized airflow through undersized ducts.

Bigger is not safety margin. It is a different failure mode.

8. What a fair quote looks like

A quote you can actually evaluate is itemized. At minimum it should separately show:

• Equipment make, model number, AFUE rating, and BTU capacity
• Labor
• Venting materials and work, if the tier requires it
• Any ductwork, gas line, or electrical modifications
• Permit fee, and who is pulling it
• Removal and disposal of the old unit
• Equipment warranty and labor warranty, stated separately — they are different lengths
• Whether the contractor is filing the Nicor rebate or leaving it to you

A single lump-sum number with a brand name attached isn't a quote you can compare against another one. Two bids that differ by $2,000 might be the same job priced differently, or two genuinely different scopes — and you can't tell which without line items.

Get three quotes. On a purchase in this range, the spread between the first and third is routinely larger than a day of your time is worth.

9. Questions to ask before you sign

1. Did you perform a Manual J load calculation, and can I see it? If the answer is a rule of thumb or the old unit's size, that's a flag.
2. Is a permit required for this scope, and are you pulling it? Especially on any high-efficiency conversion in Glenview.
3. What's your license number, and can I have a certificate of insurance? Confirm the insurance names you or your property.
4. What exactly changes about my venting, and where does the new vent exit? You want to know before there's a hole in your siding.
5. What happens to my water heater's venting? If they shared a flue, removing the furnace from it changes how the water heater drafts. This gets overlooked and it matters.
6. What's covered under labor warranty versus equipment warranty, and for how long?
7. Does this model qualify for the Nicor rebate, and will you file it?
8. What's the total, itemized?

10. Frequently asked questions

Roughly $3,800 to $12,000 installed, depending mainly on efficiency tier. A standard 80–89% AFUE furnace runs about $3,800–$6,200 installed, a 90–95% unit about $5,200–$8,800, and a 96%+ high-efficiency unit about $7,500–$12,000. Chicago-area labor tends toward the upper half of those ranges, and North Shore pricing above Chicago proper.

Not for a like-for-like replacement. The Village of Glenview does not require a permit to remove and replace HVAC equipment of the same type, size, and location without modifying exhaust venting. A permit is required if type, size, or location changes, or if venting is modified — which includes essentially every upgrade from a conventional furnace to a high-efficiency condensing model, since those require new PVC venting.

No. The Section 25C Energy Efficient Home Improvement Credit applied to qualifying property placed in service before December 31, 2025, with gas furnaces eligible for up to $600. It is not available for equipment placed in service in 2026. Utility rebates are separate and still available. Confirm your own tax position with a professional.

For the 2026 program year, $150 for a furnace at 95% AFUE or higher and $225 at 97% or higher. Bundling an ENERGY STAR smart thermostat raises those to $200 and $275. Equipment must be installed during the 2026 calendar year and the application filed within 90 days of installation.

It depends on your house. High efficiency roughly doubles installed cost, and in 2026 it no longer carries a federal tax credit to offset that — only a $150–$275 Nicor rebate. For a large, older, leaky home with a long Chicago-area heating season, fuel savings often still justify it. For a smaller or well-insulated house, the payback period is long. Note that the rebate threshold starts at 95%, so stopping at 90–94% gets you the higher cost and the permit requirement without the rebate.

No. A Department of Energy standard requiring 95% AFUE for residential non-weatherized gas furnaces was upheld in court on November 4, 2025, with a compliance date of December 18, 2028. It applies to manufacturing, not installation — there is no sell-through or installation deadline, and existing stock can still be installed afterward. It does not affect furnaces already in homes.

That should come from a Manual J load calculation, not from matching the old unit's size. Capacity runs from roughly 40,000 BTU for homes up to 1,200 square feet to 90,000–120,000 BTU for homes of 2,500–3,000+ square feet, but the correct number depends on insulation, windows, air leakage, and design temperature. Oversizing causes short cycling, uneven heating, and faster wear — it is not a safety margin.

A straightforward like-for-like swap is typically a single day. A high-efficiency conversion takes longer because it involves running new PVC venting, creating an exterior vent penetration, adding a condensate drain, and often reworking the flue a water heater was sharing. Ask the contractor for their estimate in writing along with the quote.