Do I need a permit for HVAC work in
Concord, New Hampshire?

Concord HVAC permits—the key details

Concord requires a permit for any HVAC installation, replacement, repair, or ductwork modification affecting heating, cooling, or ventilation in residential properties. This includes furnace swaps, air-conditioner upgrades, mini-split installations, heat-pump conversions, and new ductwork or modifications to existing systems. The rule is anchored in the 2015 International Energy Conservation Code (IECC 101.1) and the New Hampshire Building Code (which adopts the IRC with state amendments). Unlike some New Hampshire towns that exempt straightforward furnace-for-furnace replacements under a certain cost threshold, Concord's Building Department applies the same permit standard to all mechanical work. The logic is straightforward: HVAC systems are tied to combustion safety, electrical integration, refrigerant handling, and energy code compliance—all of which require inspection. Owner-occupants pulling permits for their own primary residences are allowed and encouraged; the city does not require a licensed mechanical contractor license for the permit filing itself, only for the actual work if refrigerant or sealed systems are involved. If you hire a contractor, they will pull the permit as part of their standard process.

State law (RSA 21:34-a) prohibits unlicensed individuals from handling refrigerant systems, performing evacuations, or working on compressor lines—this supersedes any local exemption and affects nearly all air-conditioning and heat-pump work. EPA Section 608 certification is mandatory for anyone opening a sealed system or handling more than a trace amount of refrigerant. This means owner-occupants can legally replace a furnace solo, but cannot legally perform refrigerant charging, evacuation, or compressor work on their own AC system. The state licensing requirement also means that budget contractors or handymen offering HVAC work under the table face significant liability if anything goes wrong; your recourse as a homeowner is virtually zero if the work fails and no permit was pulled. Concord Building Department staff will confirm contractor licensing during plan review and often cross-check the Heating, Ventilation, Air Conditioning and Refrigeration (HVACR) Board's license database. Many homeowners assume a simple AC replacement is exempt because it's a "like-for-like swap"—this is false in Concord and across New Hampshire.

Concord's climate zone (6A, 48-inch frost depth) creates specific HVAC siting and installation rules that are easy to miss. Outdoor condensing units must be placed with at least 2 feet of clearance on all sides (per IECC 403.8 and ASHRAE 15 standards) and cannot drain directly onto adjacent properties or into building foundations; the glacial, granite-heavy soil in the Concord area drains poorly in winter, so condensate backup and icing are common problems. If you're replacing or installing a new outdoor unit, the city will inspect for proper clearance, drainage slope, vibration isolation (especially if mounted on a deck or near a bedroom window), and setback from property lines—requirements that are enforced more strictly in Concord than in towns further north or south. Roof-mounted units (common on cape or ranch homes in the area) require structural calculations showing that the added weight doesn't exceed roof capacity; these calculations must be submitted with the permit application. Indoor ducting modifications also trigger inspection, particularly in older Concord homes where ductwork may run through unconditioned basement or attic spaces—the code requires proper sealing, insulation, and support to prevent energy loss and condensation.

The permit application itself is straightforward. You fill out the city's standard permit form (available on the Concord Building Department website or in person), provide a plan sketch showing the equipment location, clearances, and drainage, and submit a copy of any contractor's license or EPA certification. For a replacement, you may only need a one-page sketch; for a new install or ductwork redesign, the city prefers a full mechanical plan (drawn to scale, showing ductwork runs, register locations, and outdoor siting). The application fee is typically $75–$200 for a replacement and $200–$500 for a new system or major ductwork modification, calculated as a percentage of the project valuation (usually 1-2%). Online filing via the city's permit portal is available; turnaround is 5-10 business days for routine projects. Once approved, you schedule the inspection with the Building Department. Inspections are typically one-shot events: the inspector verifies equipment nameplate data, checks clearances and drainage, tests the thermostat and controls, and confirms that any electrical work (e.g., a new 240V disconnect or circuit) meets the NEC. Most inspections take 30-45 minutes. If the inspector finds an issue (e.g., inadequate clearance or improper ductwork sealing), you'll receive a 'correction notice' and must re-schedule; however, most routine replacements pass on the first inspection.

Owner-occupants in Concord can absolutely pull and manage their own permits; the city does not restrict owner-filing to single-family homes and actively encourages homeowners to engage with the process. You do not need a contractor license to file the permit—only to perform the actual mechanical and refrigerant work. This is a common point of confusion: the permit filing (the paperwork) is separate from the work (the hands-on installation). Many owner-occupants hire a contractor to do the work and have the contractor pull the permit; others file the permit themselves and then hire a contractor. Either way, the city will inspect. If you're considering DIY work, be realistic: furnace replacements and ductwork modifications are within reach for handy homeowners, but refrigerant work (charging, evacuation, leak detection) is not legal for unlicensed individuals. Heat-pump installations, which often involve both refrigerant and electrical work, are best left to licensed contractors unless you hold a current EPA 608 certificate. The city also requires proof of insurance for contractors; homeowner policies typically do not cover contractor liability on your property, so confirm that your contractor carries general liability and HVAC-specific coverage before signing a contract.

Three Concord hvac scenarios

Concord's frost depth and outdoor HVAC unit placement: why 48 inches matters

Concord sits in IECC Climate Zone 6A with a frost depth of 48 inches—one of the deepest in southern New Hampshire. This directly affects how outdoor condensing units, pad placement, and drainage must be designed. Units mounted on concrete pads that are not installed below the frost line risk heaving and settling as ground water freezes and thaws; over time, this movement stresses refrigerant lines and vibration isolators, leading to leaks and early system failure. The Concord Building Department requires outdoor units to be mounted on concrete pads installed at or below the frost line (or on pilings driven past it); many homeowners and contractors underestimate this requirement and place units on shallow 4-6 inch pads, which the inspector will reject.

Condensate drainage is equally critical in Concord's climate. Air-conditioning condensate that pools around the unit in spring and fall can freeze during early-morning or late-season temperature swings, blocking drainage and potentially backing up into the unit. The city requires condensate to be routed away from the building foundation and downslope from the unit via a sloped drain line (minimum 1/4 inch drop per 12 inches of run, per ASHRAE standards). In Concord's glacial, granite-heavy soil, water drainage is often poor; the inspector will verify that drainage does not pool on the property or toward a neighbor's foundation. Properties on steep lots or in flood-prone areas (Concord's Flood District includes portions near the Merrimack and Contoocook rivers) may face additional restrictions; the Building Department may require a certified drainage plan if the unit is close to a wetland or flood boundary.

Outdoor unit clearances are also tied to climate. The 2-foot minimum clearance on all sides (per IECC and ASHRAE 15) ensures that snow accumulation, ice damming, and seasonal leaf debris don't block air flow. In Concord, the inspector will pay particular attention to units sited near downspout discharge areas, which concentrate snow melt and ice. Units mounted on roofs or elevated decks are common in Concord (where basement or crawl-space condensers aren't viable); these require additional structural evaluation and windbracing, especially given Concord's exposure to nor'easters and the occasional ice storm. If your unit is within 3 feet of a bedroom window, Concord code (consistent with the 2015 IECC) requires vibration isolation and noise attenuation—either isolation pads or a free-standing sound barrier—to limit sleep disruption from the compressor hum.

Contractor licensing, EPA certification, and insurance in Concord—what you need to verify

Any HVAC contractor performing work in Concord must hold a current New Hampshire HVACR license (issued by the state, not the city) and EPA Section 608 certification for refrigerant handling. The state license requires passing an exam covering safety, code, and trade knowledge; EPA 608 certification is a separate credential (Type I, II, III, or Universal—Universal is most common for residential). Concord's Building Department will cross-check the contractor's license number against the state database during permit review; if the license is expired or absent, the city will reject the permit application and require you to hire a licensed contractor or pull the permit in the contractor's name. Many homeowners ask whether they can hire an unlicensed 'helper' to work alongside a licensed contractor; the answer is no—only state-licensed personnel can oversee refrigerant work, and any work performed without a valid license voids your insurance coverage and can result in stop-work orders.

Insurance is a critical issue that most homeowners overlook. Your homeowner's policy does NOT cover contractor liability on your property; you need to verify that your hired contractor carries general liability insurance ($1 million minimum is standard) and HVAC-specific coverage. Ask for a certificate of insurance (COI) before work begins; the COI should name your address as an 'additional insured' and confirm coverage for the specific scope of work. If the contractor declines to provide a COI or claims they're 'too small' to carry insurance, walk away—this is a sign of an unlicensed operator. Unpermitted or unlicensed HVAC work also creates a liability gap: if the system malfunctions and causes property damage (e.g., a refrigerant leak causes indoor air quality issues, or a condensate backup damages drywall), your homeowner's policy may deny the claim if it discovers that the work was unpermitted or done by an unlicensed contractor.

Concord's Building Department also tracks contractor complaints through the city's online permit portal and code-enforcement hotline. If a homeowner files a complaint about subpar work (poor sealing, inadequate clearance, excessive noise), the Building Department may contact the contractor's state licensing board and request an investigation. This creates a secondary motivation for contractors to do things right: one complaint can lead to license suspension or revocation. As a homeowner, you benefit from this system—if your contractor takes shortcuts or leaves you with a non-functional system, you have recourse through both the city and the state licensing board. Document all communications, take photos of the finished installation, and request a final inspection report from the Building Department; these records are valuable if you later need to pursue a complaint or civil claim.

Common questions