In Delaware, roofing permits are local—many simple reroofs don’t need a permit, but once you repair/replace more than 25% of the sheathing in New Castle County (as one example), permitting kicks in. Always check your local authority first.
Delaware’s permitting landscape
Delaware doesn’t run roofing permits centrally. Counties and municipalities adopt ICC model codes and set their own processes. That means a home in Wilmington, a store in Newark, and a rental in Rehoboth can have different administration and submittal rules—even though the technical code basis is similar. Start with your local building department before you schedule materials.
New Castle County example: the 25% sheathing rule
New Castle County’s published guidance states no building permit is required when replacing roof covering only, provided you’re not repairing/replacing more than 25% of the sheathing. Cross that threshold and you’re in permit territory for inspections and documentation. This rule often determines whether a fast shingle-over (or simple tear-off/replace) stays paperwork-light or requires extra steps.
Wilmington specifics
If your property sits within Wilmington city limits, work is administered by the Department of Licenses & Inspections. The city requires permits for new structures and many changes to existing structures; always confirm roofing classification and any inspection checkpoints before starting. Property managers handling multifamily or rentals should also align with rental inspection timelines.
Why the permit question matters
- Code compliance: Permits ensure your roof uses acceptable underlayments, fasteners, and ventilation. That’s not red tape—it protects shingle life and interior moisture control.
- Appraisals & closings: Unpermitted structural changes can delay sales.
- Insurance claims: After storms, carriers may ask for documentation. A permitted job is easier to verify.
What typically triggers permits
- Extensive decking repairs (e.g., rot after a leak).
- Structural changes (adding a dormer, altering truss members).
- Commercial reroofs where IBC and ASCE 7 wind calculations, edge metal, and tested assemblies apply.
What often doesn’t (but verify):
- Like-for-like roof covering replacement with no significant sheathing repairs in certain jurisdictions (e.g., New Castle County’s 25% rule).
How to proceed
- Call your local building department and describe scope (tear-off layers, deck repair estimate, material).
- Ask if an ice barrier is required for your assembly and location.
- Request inspection checkpoints (nail off, underlayment, final).
- If in Wilmington, coordinate timelines with Licenses & Inspections and confirm rental inspection overlaps, if applicable.
Bottom line
Permits in Delaware are straightforward once you know your jurisdiction’s thresholds. Confirm the 25% sheathing rule (or equivalent) where you live, document the work, and keep your closing packet and insurance file neat.
