Do I Need a Permit for That? HVAC, Plumbing and Electrical Permits in Delaware

In Delaware, repairing what already exists generally does not need a permit, and replacing equipment, adding capacity or changing a system does. The complication is that Delaware has no single statewide residential permit office. Building and HVAC permits come from your county or town, plumbing is permitted by the state, and electrical is handled differently again. Your local code office is the final word. 

On this page:

• Who issues permits in Delaware

• Find your authority

• Jobs that almost always need a permit

• Jobs that usually do not

• Who pulls the permit and what inspection involves

• Checking a Delaware contractor's license

• FAQs

Most permit articles about Delaware get one thing badly wrong. They describe a statewide rule, because that is how permits work in a lot of states, and Delaware is not one of them.

Delaware adopts building codes at the county and municipal level rather than at the state level, and smaller towns generally defer to their county. So the honest answer to "does Delaware require a permit for this" starts with a question: which trade, and which address.

Who Issues Permits in Delaware

Three trades, three different answers. This is the part that catches people out, including people who have permitted work in Delaware before.

Building and HVAC Permits: Your County or Town

Mechanical work, which is where furnace, boiler, air conditioner and heat pump replacements live, is permitted under the building code adopted locally. 

That means New Castle, Kent or Sussex County in unincorporated areas, and the incorporated city or town within its own limits. There is no state office that issues a residential HVAC permit for you, and there is no single Delaware answer that overrides your county's.

Plumbing Permits: Usually the State

This one surprises almost everyone. Delaware's Division of Public Health runs a Plumbing Program that permits and inspects plumbing installations statewide, except in places where a local jurisdiction operates its own plumbing program. 

So for most Delaware addresses, a plumbing permit is a state permit rather than a county one, applied for by a Delaware-licensed plumber or, in limited circumstances, by an owner-occupant. If your address falls inside a municipality that runs its own program, that municipality is the authority instead.

Electrical Permits: Licensed Electricians and Inspection Agencies

Electrical is the one that most often gets described incorrectly by out-of-state sources. 

New Castle County's own permit guidance states plainly that the county does not permit or inspect electrical work, and that State of Delaware licensed electricians are required to have their electrical work inspected by a licensed inspection agency. Kent County's permitting guidance for single family dwellings similarly says that utilities permits for electrical and plumbing are issued only by the State of Delaware and that the subcontractor obtains them. 

Practically, that means your electrician arranges inspection through an agency licensed by the Delaware Board of Electrical Examiners rather than filing an electrical permit with the county building office. It is a real difference, and it is why "I called the county about my panel and they said they do not do that" is a conversation Delaware homeowners actually have.

Find Your Authority

Start with whether your mailing address is inside town limits. If it is, the town is your authority. If it is not, the county is. 

• New Castle County (unincorporated areas): the Department of Land Use handles permits and inspections.

• Kent County: the Inspections and Enforcement Division.

• Sussex County: the county building permits office.

• Incorporated municipalities issue their own within their limits, including Wilmington, Newark, Dover, Middletown, New Castle, Elsmere, Newport, Delaware City and others. New Castle County publishes a list of local permitting jurisdictions for the northern county.

• Plumbing, statewide: the Division of Public Health Plumbing Program, except where a local jurisdiction runs its own.

• Electrical inspection: agencies licensed by the Delaware Board of Electrical Examiners and recognized by the State Fire Marshal.

Whatever the office for your address tells you supersedes this page, including where this page and that office disagree.

Jobs That Almost Always Need a Permit

The common thread is straightforward: these jobs involve gas, combustion venting or the electrical service, and an inspector is the only independent check that the work was done correctly.

Water heater replacement. A gas or electrical connection plus venting. Water heater replacement is permitted and inspected as a matter of course, and in most of Delaware that is a state plumbing permit.

Furnace, boiler, air conditioner or heat pump replacement. New equipment, new connections and often new venting or a new circuit. This is county or municipal mechanical permitting.

Electrical panel replacement or service upgrade. Always inspected, and the utility is usually involved in disconnecting and reconnecting the service. Panel replacement and service upgrades should never be done without inspection.

New branch circuits. A kitchen or bathroom remodel, EV charger installation, a hot tub, or a dedicated circuit for new equipment.

Water or sewer service line replacement. Connects to the public system, and sewer line replacement usually needs right-of-way or excavation approval as well as a plumbing permit.

Gas line additions or extensions. Permitted, and the pressure test is witnessed at inspection. Any gas line work falls here.

Jobs That Usually Do Not

These are the everyday jobs that generally proceed without paperwork.

Like-for-like fixture swaps. Faucets, toilets, garbage disposals, showerheads, in the same location with no change to the rough-in.

Thermostat replacement, including smart thermostats, as long as no new wiring is run. 

Light fixture and ceiling fan replacement on an existing box rated for the load. 

Repairs to existing equipment. A capacitor, an igniter, a heating element, a thermocouple, or a breaker of the same rating. This is what most plumbing repair and electrical repair work consists of.

Routine maintenance. Tune-ups, drain cleaning, filter and humidifier pad changes.

The line is consistent enough to remember: repairing what exists is generally not permitted work, and replacing or adding is.

Delaware Permits by Job

A compressed version of everything above. Your local code office is still the authority.

If your job is in the top half of that table, we handle the permit and meet the inspector as part of the work. Call 1-800-642-4419.

Who Pulls the Permit

Your licensed contractor should, and this is worth insisting on rather than treating as a formality.

A contractor who asks the homeowner to pull the permit is shifting liability for the work onto the homeowner. In most jurisdictions a homeowner permit carries a declaration that you performed the work yourself, which is both untrue and unhelpful if something later fails. 

There is also a useful signal buried in it. If a code office will not issue to a particular contractor, that answers the question of whether to hire them, and it answers it before the work starts rather than after.

What the Inspection Actually Involves

For most residential replacements the inspector works through a short list: correct equipment listing and clearances, proper venting and combustion air, correct circuit and overcurrent protection, bonding and grounding, and on gas work a pressure test held for the required period. 

It is usually a single visit, it happens after the work is complete and before the job is closed out, and a competent contractor schedules it without you having to ask.

What Happens If Work Was Done Without a Permit

Unpermitted work usually surfaces at resale, when a home inspector or the buyer's lender notices equipment with no permit history behind it.

The remedy is normally a retroactive permit and an inspection, with anything that does not pass having to be corrected first. That is a worse experience than permitting the job when it happened, and it arrives at the least convenient possible moment, which is during a sale with a closing date attached.

How to Check That Your Contractor Is Licensed in Delaware

Delaware licenses plumbing and HVACR work through the Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners, which issues master plumber, master HVACR and master restricted HVACR licenses. Electrical work is licensed separately through the Board of Electrical Examiners, which issues apprentice, journeyperson, master and limited electrician licenses and also licenses the inspection agencies. 

Three checks, in order of usefulness:

1. Ask for the license number and the exact name it is held under, then verify it yourself through the state's license lookup rather than accepting a photocopy.

2. Ask for a certificate of insurance sent to you directly by the insurance agency, not forwarded by the contractor.

3. Confirm in writing that the contractor is pulling the permit and scheduling the inspection.

If any of the three produces hesitation, you have learned something worth knowing.

Why Choose Horizon Services

Our technicians are licensed, insured and background checked, and we pull permits and meet inspectors on every job that needs one across Delaware, southeastern Pennsylvania, South Jersey and parts of Maryland. 

Whether it is heating services, air conditioning services, plumbing or electrical inspections, the permit is our job rather than yours. Call 1-800-642-4419, and see our ways to save page for current programs.

Delaware Permit FAQs

What are the plumbing permit requirements in Delaware?

Plumbing in Delaware is permitted and inspected by the state Division of Public Health Plumbing Program, except where a local jurisdiction runs its own program. Replacing a water heater, moving or adding a fixture, repiping, or replacing a water or sewer service line generally requires one. Like-for-like faucet and toilet swaps generally do not.

What are the HVAC permit requirements in Delaware?

Replacing a furnace, boiler, air conditioner or heat pump generally requires a permit and inspection, because the work involves gas or electrical connections and venting. Delaware has no statewide mechanical permit office, so the permit comes from your county code office or, inside town limits, from your municipality. Tune-ups and component repairs do not.

What are the electrical permit requirements in Delaware?

Panel replacements, service upgrades and new branch circuits all require inspection in Delaware. New Castle County states that it does not permit or inspect electrical work and that state-licensed electricians must use a licensed inspection agency instead. Replacing a fixture, switch, receptacle or same-rating breaker generally does not.

What are the HVAC contractor licensing requirements in Delaware?

Delaware licenses HVACR work through the state Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners, which issues master HVACR and master restricted HVACR licenses. As a homeowner the practical check is simpler: ask for the license number, verify it at dpronline.delaware.gov, and confirm the contractor is pulling the permit.

Who pulls the permit, me or my contractor?

Your licensed contractor should pull it. A contractor who asks you to pull the permit is shifting liability for the work onto you, and in most jurisdictions a homeowner permit carries a declaration that you performed the work yourself. Confirm in writing who is filing the permit before work starts.