ADU Rules in Utqiaġvik (Barrow), Alaska

Utqiaġvik (formerly Barrow) is the northernmost city in the United States, located 330 miles north of the Arctic Circle. The city is governed by the North Slope Borough. ADU construction here faces the most challenging environment in the country — continuous permafrost, extreme cold (to -60°F), and complete reliance on air freight for materials.

Permitted ADU Types

The North Slope Borough permits residential accessory structures where feasible:

• Elevated Detached Structure: Must be built on pilings above permafrost
• Attached Addition: Structurally connected to the primary dwelling's piling system
• Modular/Prefabricated: Factory-built units designed for Arctic conditions

Size Limits

Contact the North Slope Borough Planning Department for current size standards.

Permafrost Requirements

All construction in Utqiaġvik must address continuous permafrost:

• Piling foundations required: Steel or treated timber pilings driven into permafrost
• Elevated floor: Structure must be elevated to allow cold air circulation beneath
• Thermal design: Must prevent heat from the building from thawing permafrost
• Geotechnical survey: Required to determine piling depth and spacing

Extreme Cold Design

• Temperatures reach -40°F to -60°F with wind chill much colder
• All mechanical systems must be rated for Arctic temperatures
• Super-insulated building envelope required
• Utility connections may use heated utilidors (insulated utility corridors)

Climate

• No trees above the Arctic Circle — all lumber and materials arrive by air or sealift
• Extreme construction costs (often 3–5× Alaska average)
• Construction season limited by extreme cold and darkness

Permit Process

1. Contact North Slope Borough: Discuss your project before planning
2. Geotechnical survey: Essential to determine permafrost conditions
3. Arctic engineering: Engage engineer experienced in Arctic construction
4. Submit plans: Structural, mechanical, and site plans
5. Borough review: Compliance with cold climate and permafrost standards
6. Construction: During feasible season with pre-arranged materials
7. Inspections: Required per borough standards

Contact

North Slope Borough Planning Department P.O. Box 69, Utqiaġvik (Barrow), AK 99723 Phone: (907) 852-0422 Website: north-slope.org/departments/planning-department

Disclaimer: Construction in the Arctic requires extraordinary expertise and cost. Consult with the North Slope Borough Planning Department and experienced Arctic engineers before any project.