New Castle County building department

The New Castle County Department of Land Use reviews plans, issues building, demolition, plumbing, HVAC, sign, pool, and use permits, and inspects construction in unincorporated New Castle County. Its counter is in the Government Center at 87 Reads Way, open Monday–Friday, 8 a.m.–4 p.m.

County or city jurisdiction?

The county’s permits and contractor licenses cover unincorporated land only. To check a parcel, open the county’s Parcel Search: the municipality appears at the top of the parcel details page. A property inside an incorporated town’s tax area is not county jurisdiction. Wilmington, Newark, and Middletown each run their own permit offices.

What needs a permit

All construction needs a permit, including new buildings, interior and exterior improvements, alterations, and most repairs, unless Section 06.03.012 of the County Code (Chapter 6) exempts the work. If your project isn’t on the exempt list, assume you need a permit. Two other agencies handle parts of most projects:

• Electrical work: The county doesn’t permit or inspect it. Licensed electricians have their work inspected by a state-licensed inspection agency. An owner-occupant doing their own electrical work gets a homeowner permit from the State of Delaware.
• Driveways and sidewalks: New or modified ones may need a DelDOT entrance permit.

Deed restrictions are the owner’s responsibility to check before applying. The county doesn’t enforce them.

Common exemptions (Chapter 6, as amended through January 1, 2026)

Project	No permit needed when
Shed, playhouse, pergola, gazebo	One story, detached, 200 sq ft or less, eave 10 ft or less, overall height 20 ft or less. Garages and anything that can store a vehicle don’t qualify
Deck	200 sq ft or less, no more than 30 in. above grade at any point, and not attached or adjacent to the house
Fence	Always exempt, except a swimming pool barrier
Retaining wall	4 ft or less of exposed height, with no surcharge
Re-roof or new siding	No more than 25% of the sheathing repaired or replaced. The siding exemption excludes stone, masonry veneer, and stucco
Windows and doors	Same size and location, with the structural frame unchanged
Patio, slab, hardscape	Non-structural and no more than 30 in. above grade
Carport or patio cover	Free-standing, prefabricated, 200 sq ft or less, and open on at least two sides
Other	Sidewalks and driveways, deck board and railing replacement, rooftop solar panels on one- and two-family homes, EV charging stations, painting, flooring, cabinets, and countertops

Exempt work must still meet zoning setbacks. Properties in a Historic overlay district need historic review even for exempt work.

Applying through eServices

Building, demolition, and utility permits that need plan review go through eServices, a ProjectDox system at eplans.nccde.org. Use, special event, and outdoor sales permits are filed separately. So are utility permits with no plan review, which go through a separate online portal.

1. Create an account and submit the application in eApply.
2. Watch for an email inviting you into the ePlans project. The applicant named on the application must be the person who logs in to ePlans.
3. Upload plans and documents. Save each sheet as a separate PDF.
4. Staff run a prescreen for completeness, then route the plans to every review discipline at once.
5. Upload corrections, if required. Each resubmittal is prescreened again.
6. After final review and payment, the permit and approved plans are available to download in ePlans.

The county offers in-person help through QLess virtual-line appointments, which start at 8:30 a.m. These sessions help you enter a permit into ePlans but don’t include plan review.

Residential additions and accessory structures

The county’s requirements sheet (rev. 11/04/2025) asks for:

• A building contractor license, or an Owner-Occupier Affidavit
• Building plans
• A current plot plan signed and sealed by an engineer or surveyor
• A sealed Lines and Grades plan and checklist for buildings and additions of 480 sq ft or more
• DNREC septic capacity approval when adding bedrooms on a septic system
• A separate demolition permit for any demolition work
• A DelDOT entrance permit when the work changes or adds a street entrance

The county also publishes sample drawings for decks, rear additions, basement finishes, and garage conversions.

Adopted codes

Code	Edition	Effective
International Building, Residential, and Existing Building Codes, and Swimming Pool and Spa Code	2024	Jan. 1, 2026
International Mechanical, Fuel Gas, and Plumbing Codes	2021	Jan. 1, 2024
International Energy Conservation Code	2018	Jan. 1, 2021

Chapter 6 of the County Code contains the local amendments. Detached one- and two-family homes and townhouses up to three stories follow the IRC, and everything else follows the IBC. The county posts ICC staff code interpretations it has requested on a Code Opinions page.

Fees

Fee	Amount
Building permit, first $1M of valuation	$12 per $1,000
Building permit, valuation above $1M	$5.25 per $1,000
Zoning review	10% of the valuation fee ($21 min., $145 max.)
Certificate of occupancy	$60
Volunteer Fire Assistance Fund	0.5% of the valuation fee
Mechanical or plumbing permit	$5.25 per $1,000 ($65 min.)
Permit extension	$80
Working without a permit	Permit fee plus an equal penalty ($300 min. for contractors)

Pay fees online. Since July 1, 2026, credit card payments carry a 3% vendor fee. ACH and e-check payments don’t.

Permit time limits

Permit type	Start within	Finish within
Residential new construction	180 days	1 year
Residential additions and accessory structures	45 days	1 year
Residential decks	30 days	90 days
HVAC, plumbing, demolition, signs, pools	30 days	90 days
Non-residential tenant fit-outs	45 days	180 days

The permit is treated as abandoned after 30 days with no work. The Code Official can grant extensions of up to 180 days each.

Contractor licensing and owner-builders

Contractors working in unincorporated New Castle County need a county license:

• Permit-endorsed license: for builders, plumbers, HVACR contractors, and other trades whose work needs a permit
• Non-permit-endorsed license: for other construction trades (NAICS Sector 23)

Electricians are licensed by the state instead. The county runs an online Contractor License Search. Licensing questions go to (302) 395-5420.

Owner-occupiers who aren’t selling or renting any part of the home can pull their own permits for accessory structures, additions, renovations, and demolition. They can also take plumbing permits for their own home, except for gas piping. Building your own new house is allowed as a one-time exemption that the Code Official must approve.

Inspections

County inspectors handle building, mechanical, plumbing, and site inspections. Schedule them any time at inspections.newcastlede.gov. The same site shows permit status, real-time results, and fees due, and lets you upload documents for permits with conditions. On inspection day, you get an email at 7 a.m. with the estimated time and your assigned inspector. Questions go to the Office of Inspections at (302) 395-5572. A building can’t be occupied until it passes final inspections and receives a temporary or permanent certificate of occupancy.