If your construction business operates or is expanding into Delaware, you’ll need to understand the state’s building permit process. Delaware has no statewide building code enforcement — each jurisdiction manages permitting individually. For contractors, developers, and builders, this means requirements vary between counties and cities, making it critical to check with the local authority having jurisdiction (AHJ).
Below, learn about what construction work requires a Delaware building permit, who issues them, costs, unique considerations, and the step-by-step process to pull a permit.
Who issues building permits in Delaware?
Permitting authority in Delaware is handled at the county or municipal level.
- Counties: New Castle, Kent, and Sussex counties each issue permits for unincorporated areas.
- Municipalities: Larger cities like Wilmington, Newark, and Dover manage their own permitting processes.
If your project falls within an incorporated city or town, you must work directly with that local building department.
When do you need a Delaware building permit?
Most construction and major renovation projects require a building permit in Delaware.
Common projects include:
- New residential or commercial construction
- Additions, alterations, or structural remodels
- Accessory structures (garages, sheds, decks, porches)
- Roofing projects that alter structural components
- Swimming pools, fencing, and retaining walls over a certain height
- Electrical, plumbing, and HVAC system installations (separate trade permits may apply)
- Demolition of existing buildings or structures
Routine maintenance, cosmetic work (painting, flooring), and non-structural repairs often do not require a permit, but rules vary by jurisdiction.
Delaware building permit requirements
While requirements vary, most jurisdictions will request:
- Completed permit application form
- Construction drawings or blueprints (stamped by a licensed architect/engineer for commercial projects)
- Site plan with property lines, setbacks, and easements
- Contractor license or registration documentation
- Energy code compliance forms (Delaware follows the 2018 International Energy Conservation Code)
- Additional permits or approvals: zoning, stormwater management, and state agency approvals in certain cases (especially coastal or environmentally sensitive sites)
Delaware building permit costs
Permit fees differ depending on jurisdiction and project size.
Common permit fee structures include:
- Valuation-based fees: Calculated as a percentage of construction cost
- Square-footage fees: Based on the size of the project (common for new homes)
- Flat fees: Applied to smaller projects like fences or sheds
Examples of permit fee schedules in Delaware:
- New Castle County: Fees are based on construction valuation, with additional trade permit fees.
- Sussex County: Residential building permits often start at $200+, with separate electrical, plumbing, and mechanical permit fees.
- City of Dover: Follows ICC valuation tables plus local amendments.
Always check with your local building department for the most current fee schedule.
Unique considerations when permitting in Delaware
Coastal zone restrictions
Projects near beaches, wetlands, or the Delaware Bay may require additional review from the Delaware Department of Natural Resources and Environmental Control (DNREC).
Energy code compliance
Delaware enforces the 2018 IECC, with some local jurisdictions applying additional amendments.
Stormwater management
Many projects, especially in Kent and Sussex counties, require separate permits for erosion and sediment control.
How to get a building permit in Delaware
The process varies by jurisdiction, but most follow these steps:
- Determine jurisdiction – Confirm whether your project falls under county or municipal authority.
- Prepare documentation – Gather plans, site drawings, and required approvals.
- Submit application – Apply online or in person with the relevant building department.
- Zoning and site review – Planning staff review setbacks, land use, and environmental factors.
- Plan review – Building officials review compliance with IBC, IRC, and local amendments.
- Pay permit fees – Based on valuation, square footage, or flat fee structures.
- Permit issuance – Once approved, display permit on-site.
- Inspections – Schedule inspections at key phases (foundation, framing, mechanical, electrical, plumbing, final).
