Los Alamos County, NM - 2026 Building Permit Guide

Permit Authority

Los Alamos County is a consolidated city-county government. The county building division processes all building permits for private and county-owned land within county boundaries, except for federally controlled lands (DOE/LANL and National Park Service lands). A significant portion of Los Alamos County consists of federal land managed by the U.S. Department of Energy for Los Alamos National Laboratory, which falls outside county permit jurisdiction. Bandelier National Monument, also within county boundaries, is administered by the National Park Service and requires federal permits, not county permits.

Department

Los Alamos County Community Development Department, Building Permits and Inspections Division

Address

1000 Central Avenue, Suite 150, Los Alamos, NM 87544

Phone

505-662-8120

Email

building@lacnm.us

Website

https://www.losalamos.gov/174/Building-Permits-Inspections

Online Permit Portal

Application Process

1. Verify the property is on private or county-owned land (not DOE/LANL federal land or NPS land). Use the county GIS at https://www.losalamos.gov/198/Geographic-Information-Systems or contact the Building Permits and Inspections Division at 505-662-8120 to confirm land status before beginning any application.
2. Determine the permit type required for your project (building, electrical, plumbing, mechanical, grading, demolition, or combination).
3. Contact the division to obtain the current application packet and submittal checklist for your specific project type. Checklists are available at the counter or may be downloadable from https://www.losalamos.gov/174/Building-Permits-Inspections.
4. Prepare required plans and documents per the checklist. For new residential construction and commercial projects, stamped engineered or architect-prepared drawings are typically required.
5. Submit the completed application with all required documents. Online submission may be available for simple permit types; in-person submission at Suite 150 is required for complex projects.
6. Pay the applicable permit fee at time of application submittal. Plan review fees are collected at submission; remaining fees are collected at permit issuance.
7. Plans are reviewed by county building staff for compliance with adopted codes. The reviewer may issue correction comments requiring additional information or revised plans.
8. Respond to all plan review correction comments and resubmit revised documents. All correction cycles must be resolved before permit issuance.
9. Once plans are approved, pay any remaining permit fees. The permit is then issued. Post the permit card in a conspicuous location on the job site.
10. Schedule required inspections at the appropriate milestones during construction. Inspections must be scheduled in advance.
11. Complete all required inspections. The building inspector will note any deficiencies that must be corrected prior to re-inspection.
12. Upon passing all required inspections, including the final inspection, the county issues a Certificate of Occupancy (CO) for the structure.

Typical processing time: Standard residential permit review is typically completed within 10 to 15 business days for straightforward projects. Commercial and custom residential projects requiring full plan review may take 15 to 30+ business days depending on project complexity and completeness of submittal. Resubmittals for corrections add additional review cycles.

Source: Los Alamos County Community Development Department, Building Permits and Inspections Division

General Requirements

A building permit is required for all new construction, additions, alterations, repairs that affect structural elements or change the use of the structure, demolition, re-roofing, replacement of major systems (HVAC, electrical panel, plumbing), manufactured home placement, accessory structures (with limited exceptions), swimming pools, solar photovoltaic and solar thermal installations, and fences over a specified height.

Required Documents

• Completed permit application form
• Site plan drawn to scale showing property lines and dimensions, existing and proposed structures, setback dimensions from all property lines, lot coverage calculation, driveway and utility locations, grading/drainage plan if site grading is involved, and address/legal description of the property
• Construction drawings: floor plan, exterior elevations, foundation plan, framing plan, cross-sections, and construction details (stamped by a licensed NM architect or engineer for custom homes above a threshold square footage)
• Energy compliance documentation: COMcheck (commercial) or REScheck (residential) compliance report or equivalent demonstrating compliance with the NM Energy Conservation Code
• Mechanical, electrical, and plumbing layout drawings if included in the project scope
• Contractor CID license number and certificate of insurance (if using a licensed contractor); or owner-builder affidavit if the owner is self-performing the work
• Proof of legal access and E-911 address assignment if constructing on a new lot
• Soils or geotechnical report may be required for hillside sites, expansive soil areas, or larger structures given the Jemez Mountains terrain

Permit validity

Building permits are generally valid for 180 days from the date of issuance; work must commence within 180 days or the permit expires. If work is abandoned or suspended for 180 consecutive days after commencement, the permit also expires. One extension may be available upon written request with justification.

Building code

Los Alamos County, as a Local Enforcement Agency under NM CID, adopts the current New Mexico state-amended building codes: 2021 New Mexico Residential Building Code (based on 2021 IRC with NM amendments), 2021 New Mexico Commercial Building Code (based on 2021 IBC with NM amendments), 2021 New Mexico Plumbing Code (based on 2021 UPC with NM amendments), 2021 New Mexico Mechanical Code (based on 2021 IMC with NM amendments), 2020 New Mexico Electrical Code (based on 2020 NEC with NM amendments), 2021 New Mexico Energy Conservation Code (residential and commercial), New Mexico Earthen Building Materials Code (adobe and rammed earth), and 2021 International Fire Code as locally adopted and amended.

Owner-builder

Owner-builder (homeowner permit) is available in Los Alamos County for work on the owner's primary residence. The applicant must complete and sign the New Mexico CID owner-builder affidavit. Under NM state law (14.5.2.18 NMAC), an owner-builder may obtain one permit per 12 months. The owner-builder may not use the permit to sell the property within one year of permit issuance without full disclosure to the buyer.

Contractor requirements

All contractors performing construction work in Los Alamos County must hold a valid New Mexico Construction Industries Division (CID) license. Applicable license classifications include GB-2 (General Building Contractor, residential only), GB-98 (General Building Contractor, residential and commercial), EM (Electrical Mechanic/Master Electrician), PJ (Journeyman Plumber), PM (Master Plumber), GA (Gas Mechanic), and others as applicable. All contractors must provide their CID license number on the permit application.

Fees

Plan check fee

Typically calculated as a percentage of the base building permit fee at time of application submittal (commonly 65% for residential and 65% to 85% for commercial; confirm current percentage with the division)

Permit fee formula

Valuation-based. Contact the division at 505-662-8120 or building@lacnm.us for the current adopted fee resolution and specific fee amounts.

Trade permit fee

Electrical, plumbing, and mechanical permits each carry their own fees, typically calculated based on the number of fixtures, circuits, or equipment installed

Reinspection fee

Charged when a required inspection fails or when the inspector cannot gain access to the site. Amount to be confirmed with the division.

Payment note

Fees may be paid in person at the division office (1000 Central Avenue, Suite 150) by check, credit/debit card, or cash. Online payment may be available through the county's Community Development portal. Confirm accepted methods with the division.

Fees change. Verify current amounts at the official fee schedule.

Work That Does NOT Require a Permit

• One-story detached accessory structures (e.g., tool sheds, playhouses) with a floor area not exceeding 120 square feet, provided the structure is not served by utilities
• Ordinary maintenance and repair that does not affect structural elements, egress, fire protection, or life safety systems, and does not involve new or modified plumbing, electrical, or mechanical systems
• Interior finish work: painting, papering, tiling, carpeting, cabinets, countertops, and similar finish work not involving structural changes
• Fences not exceeding 6 feet in height above grade (confirm with division as WUI or fire-department standards may apply to fence materials and placement in designated hazard areas)
• Prefabricated swimming pools that are accessory to a one- or two-family dwelling, less than 24 inches deep, not over 5,000 gallons capacity, and installed entirely above ground

Important: Even where a building permit is not required, separate electrical, plumbing, or mechanical permits are required if utility connections are involved. Always confirm with the Los Alamos County Building Permits and Inspections Division at 505-662-8120 before proceeding without a permit.

Inspections

How to Schedule

• 505-662-8120 (phone)
• building@lacnm.us (email)

Scheduling deadline

Inspection requests should be submitted at least one business day in advance.

Inspection hours

Monday through Friday, 8:00 AM to 5:00 PM

Time windows

Specific inspection time windows (AM or PM) may be available upon request; contact the division to confirm.

Typical inspection sequence: Typical sequence for new residential construction: 1) Footing/foundation inspection after excavation, forms set, and reinforcing steel placed; before concrete pour. 2) Underground utility inspection before slab is poured or covered. 3) Slab inspection after sub-slab preparation and before concrete pour. 4) Framing inspection after all rough framing, roofing, rough electrical, rough plumbing, and rough mechanical are installed; before insulation or drywall. 5) Insulation inspection after insulation is installed but before drywall. 6) Drywall/wallboard inspection after drywall is hung and screwed but before taping and finishing. 7) Final building inspection when the structure is complete, all systems are operational, and all trim and finish work is done. 8) Certificate of Occupancy issued after all required inspections are passed.

Additional Resources

• Building code: Los Alamos County, as a Local Enforcement Agency under NM CID, adopts the current New Mexico state-amended building codes: 2021 New Mexico Residential Building Code (based on 2021 IRC with NM amendments), 2021 New Mexico Commercial Building Code (based on 2021 IBC with NM amendments), 2021 New Mexico Plumbing Code (based on 2021 UPC with NM amendments), 2021 New Mexico Mechanical Code (based on 2021 IMC with NM amendments), 2020 New Mexico Electrical Code (based on 2020 NEC with NM amendments), 2021 New Mexico Energy Conservation Code (residential and commercial), New Mexico Earthen Building Materials Code (adobe and rammed earth), and 2021 International Fire Code as locally adopted and amended.
• Verify contractor license: NM Construction Industries Division - Contractor Licensing
• Zoning information: View zoning info
• Owner-builder rules: View rules
• Los Alamos County Utilities (LADWP)
• Los Alamos County Fire Department
• Los Alamos County Engineering Division
• NM CID Rules and Building Codes
• NM CID Residential Permit Guide (PDF)
• County Code of Ordinances
• NM State Forestry Division - Wildfire Resources
• Los Alamos National Laboratory
• Bandelier National Monument
• License lookup guide: New Mexico Contractor License Requirements
• Contract template: New Mexico Homeowner-Contractor Agreement
• New Mexico hub: New Mexico Contractor License & Permit Hub

Frequently Asked Questions

Los Alamos County Building Permit FAQ

Do I need a building permit in unincorporated Los Alamos County, NM?

A building permit is required for all new construction, additions, alterations, repairs that affect structural elements or change the use of the structure, demolition, re-roofing, replacement of major systems (HVAC, electrical panel, plumbing), manufactured home placement, accessory structures (with limited exceptions), swimming pools, solar photovoltaic and solar thermal installations, and fences over a specified height.

How much does a building permit cost in unincorporated Los Alamos County, NM?

Fees are calculated as: Valuation-based. Contact the division at 505-662-8120 or building@lacnm.us for the current adopted fee resolution and specific fee amounts.. Plan check fee: Typically calculated as a percentage of the base building permit fee at time of application submittal (commonly 65% for residential and 65% to 85% for commercial; confirm current percentage with the division).

How do I apply for a building permit in unincorporated Los Alamos County, NM?

1. Verify the property is on private or county-owned land (not DOE/LANL federal land or NPS land). Use the county GIS at https://www.losalamos.gov/198/Geographic-Information-Systems or contact the Building Permits and Inspections Division at 505-662-8120 to confirm land status before beginning any application. 2. Determine the permit type required for your project (building, electrical, plumbing, mechanical, grading, demolition, or combination). 3. Contact the division to obtain the current application packet and submittal checklist for your specific project type. Checklists are available at the counter or may be downloadable from https://www.losalamos.gov/174/Building-Permits-Inspections. 4. Prepare required plans and documents per the checklist. For new residential construction and commercial projects, stamped engineered or architect-prepared drawings are typically required. 5. Submit the completed application with all required documents. Online submission may be available for simple permit types; in-person submission at Suite 150 is required for complex projects. 6. Pay the applicable permit fee at time of application submittal. Plan review fees are collected at submission; remaining fees are collected at permit issuance. 7. Plans are reviewed by county building staff for compliance with adopted codes. The reviewer may issue correction comments requiring additional information or revised plans. 8. Respond to all plan review correction comments and resubmit revised documents. All correction cycles must be resolved before permit issuance. 9. Once plans are approved, pay any remaining permit fees. The permit is then issued. Post the permit card in a conspicuous location on the job site. 10. Schedule required inspections at the appropriate milestones during construction. Inspections must be scheduled in advance. 11. Complete all required inspections. The building inspector will note any deficiencies that must be corrected prior to re-inspection. 12. Upon passing all required inspections, including the final inspection, the county issues a Certificate of Occupancy (CO) for the structure.

How long does it take to get a building permit in unincorporated Los Alamos County, NM?

Typical processing time is Standard residential permit review is typically completed within 10 to 15 business days for straightforward projects. Commercial and custom residential projects requiring full plan review may take 15 to 30+ business days depending on project complexity and completeness of submittal. Resubmittals for corrections add additional review cycles..

What work is exempt from building permits in unincorporated Los Alamos County, NM?

The following work is generally exempt: One-story detached accessory structures (e.g., tool sheds, playhouses) with a floor area not exceeding 120 square feet, provided the structure is not served by utilities; Ordinary maintenance and repair that does not affect structural elements, egress, fire protection, or life safety systems, and does not involve new or modified plumbing, electrical, or mechanical systems; Interior finish work: painting, papering, tiling, carpeting, cabinets, countertops, and similar finish work not involving structural changes; Fences not exceeding 6 feet in height above grade (confirm with division as WUI or fire-department standards may apply to fence materials and placement in designated hazard areas); Prefabricated swimming pools that are accessory to a one- or two-family dwelling, less than 24 inches deep, not over 5,000 gallons capacity, and installed entirely above ground. Note: Even where a building permit is not required, separate electrical, plumbing, or mechanical permits are required if utility connections are involved. Always confirm with the Los Alamos County Building Permits and Inspections Division at 505-662-8120 before proceeding without a permit.

How do I schedule a building inspection in unincorporated Los Alamos County, NM?

Inspections can be scheduled via: 505-662-8120, building@lacnm.us. Inspection requests should be submitted at least one business day in advance..