Town of Northumberland, NH - 2026 Building Permit Guide

Permit Authority

Town of Northumberland (includes the village of Groveton).

Department

Assessing Office

Address

19 Main Street, Northumberland, NH 03582

Phone

603-636-1450

Website

https://northumberlandnh.gov/assessing/

Online Permit Portal

Application Process

1. Download the Building Permit Application from the forms page.
2. Determine if a permit is required: required when the project changes the property footprint OR when anticipated material costs exceed $5,000. No permit is required for remodeling/repair work where material costs are under $5,000 and the footprint does not change.
3. Complete all sections: property details, project description, site map showing work location and setback compliance.
4. Attach elevation certificate if in a floodplain; attach approved driveway permit if a new driveway is being created; attach approved septic design if applicable.
5. Attach NH energy code certification for applicable new construction projects.
6. Submit to the Assessing Office with fee. Application is routed internally for review by Highway, Water/Sewer, Fire, Ambulance, and Police departments, then signed by the Building Inspector and three Selectmen.
7. No work may begin before permit approval unless specifically authorized by the Board of Selectmen.
8. Post the permit visibly from the highway.
9. Permits approved in 2025 are valid through March 31, 2026; if work is completed and town notified by that date, a $25 refund may be available; if work is unfinished, a free one-year renewal may be requested.

Source: Assessing Office

General Requirements

Any project that changes the property footprint, or any remodeling/repair with anticipated material costs exceeding $5,000.

Required Documents

• Completed Building Permit Application
• Property details
• Project description
• Site map showing work location and setback compliance
• Elevation certificate (if in a floodplain)
• Approved driveway permit (if new driveway)
• Approved septic design (if applicable)
• NH energy code certification (for applicable new construction)

Permit validity

Annual -- valid through March 31 of the following year.

Building code

NH State Building Code (RSA 155-A); Northumberland Zoning Ordinance (2020, updated 2025)

Owner-builder

Owner-builders may apply.

Contractor requirements

No NH GC license; state-licensed electricians and plumbers required.

Work That Does NOT Require a Permit

• Remodeling or repairs where material cost is under $5,000 and footprint does not change

Inspections

How to Schedule

• 603-636-1450 (Assessing Office) (phone)

Inspection hours

Monday, Tuesday, Wednesday, Friday 8:00 AM - 3:30 PM; Thursday 8:00 AM - noon

Typical inspection sequence: Building Inspector and Code Enforcement Officer have authority to inspect buildings, structures, and construction sites under RSA 155-A and the town's zoning ordinance.

Additional Resources

• Building code: NH State Building Code (RSA 155-A); Northumberland Zoning Ordinance (2020, updated 2025)
• Zoning information: View zoning info
• License lookup guide: New Hampshire Contractor License Requirements
• Contract template: New Hampshire Homeowner-Contractor Agreement
• New Hampshire hub: New Hampshire Contractor License & Permit Hub

Frequently Asked Questions

Town of Northumberland Building Permit FAQ

Do I need a building permit in Town of Northumberland, NH?

Any project that changes the property footprint, or any remodeling/repair with anticipated material costs exceeding $5,000.

How do I apply for a building permit in Town of Northumberland, NH?

1. Download the Building Permit Application from the forms page. 2. Determine if a permit is required: required when the project changes the property footprint OR when anticipated material costs exceed $5,000. No permit is required for remodeling/repair work where material costs are under $5,000 and the footprint does not change. 3. Complete all sections: property details, project description, site map showing work location and setback compliance. 4. Attach elevation certificate if in a floodplain; attach approved driveway permit if a new driveway is being created; attach approved septic design if applicable. 5. Attach NH energy code certification for applicable new construction projects. 6. Submit to the Assessing Office with fee. Application is routed internally for review by Highway, Water/Sewer, Fire, Ambulance, and Police departments, then signed by the Building Inspector and three Selectmen. 7. No work may begin before permit approval unless specifically authorized by the Board of Selectmen. 8. Post the permit visibly from the highway. 9. Permits approved in 2025 are valid through March 31, 2026; if work is completed and town notified by that date, a $25 refund may be available; if work is unfinished, a free one-year renewal may be requested.

What work is exempt from building permits in Town of Northumberland, NH?

The following work is generally exempt: Remodeling or repairs where material cost is under $5,000 and footprint does not change.

How do I schedule a building inspection in Town of Northumberland, NH?

Inspections can be scheduled via: 603-636-1450 (Assessing Office).

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