New Hampshire Mechanical Permits: Boilers Triple in Fall

In Concord, New Hampshire, boiler permits ran 2.4 times faster from September to December 2025 than they did from January to August. Furnace permits rose by about a third over the same break. Heat pump permits barely moved. So the heating season in New Hampshire's mechanical permit file is mostly a boiler story, and a contractor who plans around "HVAC season" as one curve is planning around the wrong one.

The data comes from Concord's mechanical permits, 1,221 of them since late 2022, because Concord is the only town in our New Hampshire file that issues that permit type at all.

TL;DR

• Concord boiler permits averaged 6.8 a month before September 2025 and 16.5 a month after it.
• Furnace permits rose from 11.5 to 15.5 a month. Heat pumps stayed near 7.
• Concord names no contractor or owner. The Seacoast names them, but files far fewer heating permits.
• New Hampshire licenses gas fitters. Oil heating technicians only have a voluntary state certification.

What does a New Hampshire mechanical permit actually record?

In our file, a mechanical permit is a Concord document. The city's Code Administration issues separate trade permits for mechanical work, and it splits them three ways: Mechanical (Residential) with 996 records, Mechanical (Commercial) with 213, and Mechanical (Homeowner) with 12. About half of the homeowner permits are owner-installed furnaces; the rest include a wood stove, two heat pump jobs and one oil boiler.

Hampton, Exeter and Seabrook do not publish a mechanical permit type. Heating work in those towns shows up, when it shows up, under plumbing, electrical or building. That single recording difference shapes everything below, and it is the reason New Hampshire permit records vary so much from town to town.

Concord also runs its own propane permit. The LP Tank Installation Permit Application accounts for 138 records since January 2025, separate from mechanical. Propane dealers and the installers who set tanks for new gas appliances will find their activity there, not in the mechanical file.

A Concord mechanical record gives you the street address, the application date and a short work description. It gives you no contractor name, no owner name and no job value. Nothing. That matters for how you use it, and we come back to it in the outreach section.

Do boiler permits really surge in the heating season?

Yes, and harder than any other heating equipment. The cleanest comparison is calendar 2025, the first full year in which Concord's mechanical series is complete in our data. We split each equipment type by the monthly average from January to August against September to December.

Equipment named in a Concord mechanical permit	Jan–Aug 2025, per month	Sep–Dec 2025, per month	Change
Boiler	6.8	16.5	2.4×
Water heater	5.4	10.0	1.9×
Furnace	11.5	15.5	1.3×
Heat pump, mini split or VRF	6.6	7.3	1.1×
Gas piping, propane or tank work	9.3	7.8	0.8×
All mechanical permits	52.1	71.8	1.4×
Building permits, for contrast	164.1	129.8	0.8×

The last two rows are the ones to read together. Building permits in Concord fall away after August as the construction season closes. Mechanical permits go the other way. A contractor who watches only building permit volume will see Concord slowing down in exactly the months its heating equipment is being replaced fastest.

Across the whole of 2025, 55% of Concord's boiler permits landed in the last four months of the year. For furnaces the figure was 40%, and for heat pumps 35%, barely above the 33% an even spread would give.

The boiler season also runs long. January 2026 added 20 boiler permits, February 10 and March 14, before the file dropped back to single digits from April. Plan for a season of five to seven months, not a single October rush.

One caution about how we counted. These are keyword matches on free-text work descriptions, so a permit that names neither "boiler" nor "furnace" is missed, and a job described loosely may land in the wrong row. Read the table as the shape of the year, not as a census of installations.

Why do boilers move and heat pumps stay flat?

Our reading is that boilers are replaced when they fail, and they fail when they are first asked to work hard. A hydronic system that limped through summer supplying domestic hot water meets its first real heating load in late September, and the permit follows the failure within days.

Heat pumps behave like a planned purchase. The buyer decides, often around an incentive, and the installer schedules it. That is why the heat pump row is flat through the year, and it is why our separate piece on NHSaves heat pump rebates treats that market as a rebate-calendar problem rather than a weather problem.

Fuel matters here. The U.S. Energy Information Administration's 2020 Residential Energy Consumption Survey found fuel oil to be the most common primary heating fuel in New Hampshire homes, at about 40%. In Concord's own descriptions, oil is named on 29 boiler permits against 16 furnace permits, so the equipment with the steepest seasonal curve is also the one most tied to the state's most common fuel.

We would not push the theory further than the data. Boiler permits did not simply track the thermometer. December 2025 was the peak at 21, but August 2026 already showed 16 boiler permits against 5 in August 2025. One early month is not a trend, and we have not established a cause. Watch it.

Where do boiler and furnace permits show up outside Concord?

Barely, and under other names. From January 2025 through August 2026, our New Hampshire file holds 540 permits describing a boiler or furnace. Concord accounts for 475 of them, and 462 of those are mechanical permits.

The three Seacoast towns together contribute 65. Hampton has 40, spread across plumbing, electrical and building permits. Seabrook has 15. Exeter has 10, all electrical or gas. That is too few to plan a season around, and too few to measure one.

What the Seacoast records have is names. Between 83% and 100% of them name a contractor, depending on town and equipment, and all of them carry a declared job value. Hampton's 17 boiler permits show a median declared value of about $11,100. Seventeen records is a small sample, so read that as a price reference point rather than a market rate.

So the two halves of New Hampshire's heating file do different jobs. Concord supplies the volume and the calendar. The Seacoast supplies competitor names and price context. Neither does both.

Which licences sit behind a New Hampshire heating job?

It depends on the fuel. New Hampshire has no state general contractor licence, a point we covered in how the state licenses trades but not builders. It does license fuel gas fitters. Under RSA 153:27 through 153:38, the Mechanical Safety and Licensing Board, part of the Office of Professional Licensure and Certification, licenses gas installation and service technicians, piping installers and trainees for natural gas and propane work.

Oil is different. State law provides a voluntary certification for technicians who install and service oil heating equipment, not a mandatory licence. So in the state where oil is the most common heating fuel, the most common heating replacement carries the lightest state credential.

That is a real selling point for a certified oil technician, and a real risk for a homeowner choosing one. It is also why the permit file matters: the town's mechanical permit may be the only public record that an oil boiler was replaced at all.

Two further details. RSA 153:36 exempts property owners working on their own single-family home from the gas fitter licence, which fits Concord's small Mechanical (Homeowner) category, where about half of the 12 records are owner-installed furnaces. And the 2024 International Mechanical Code took effect in New Hampshire on July 1, 2026, with the concurrence window for the 2021 editions closing December 31, in the middle of this year's boiler season.

How should you work New Hampshire's heating-season permits?

Start with Concord's mechanical file, filtered on the equipment you install, and treat each record as an address with a date.

A permit is a signal about the homeowner, not the contractor. In Concord that is literally all it is, because the city records neither party. A boiler replacement filed in October tells you a household just spent real money on a failed system and is living with the result. It does not tell you who did the work, and it does not invite you to compete for the job that has already been permitted.

What it does invite is the follow-on work. Hydronic controls and zoning, an indirect water heater off the new boiler, a chimney liner check for an oil-to-gas or oil-to-propane change, a generator to keep a circulator running through an outage, and an annual service agreement. Those are offers a household can say yes to in the weeks after a replacement. Speed matters with this kind of reactive record, which is the case we make in our speed-to-lead guide.

On the Seacoast, work the other way round. Read the named contractors on boiler and furnace permits to see who is winning heating work in Hampton and Seabrook, and use the declared values to sanity-check your own quotes. The HVAC contractor playbook sets out the trigger windows for the trade as a whole.

And set up for the season now, not in November. The Concord curve lifted in September last year.

How permits.llc fits in

We hold about 13,200 New Hampshire permit records across Concord, Hampton, Exeter and Seabrook, in Merrimack and Rockingham counties. Concord runs back to October 2022, and the three Seacoast towns to January 2025. That is four towns, not the whole state.

Within them, Concord's mechanical file is the only continuous New Hampshire record of heating equipment being replaced, and you can browse it by type on our New Hampshire mechanical permit page.

Pull the records yourself from the New Hampshire permit download, or set up New Hampshire permit alerts so new Concord boiler and furnace permits reach you in the same week they are filed.