Longmont building permit requirements

Tips & gotchas

• Longmont physically straddles Boulder County and Weld County — but permitting authority does NOT vary by county. The City of Longmont (a home-rule municipality) is the sole building-permit authority citywide through its Building Services division, regardless of which county a given parcel falls within. This PermitBase entry is filed under Boulder County for URL/geographic routing purposes only.
• Longmont runs its OWN municipal electric utility, Longmont Power & Communications (LPC) — unlike most Colorado cities served by Xcel Energy or a rural electric co-op. LPC is a mandatory reviewer for solar PV interconnection (one-line diagrams, checklists) and has EXCLUSIVE authority over electric meter sets/removals and service disconnects/reconnects citywide — contractor or homeowner attempts at these specific tasks are treated as meter tampering with potential fines and criminal referral.
• As of this extraction (2026-06-30), Longmont's currently ADOPTED AND EFFECTIVE base code is still the 2021 International Codes (effective Jan 1, 2022) — NOT the 2024 codes. The city's own Building Code Update page describes 2024 code adoption (plus the Colorado Energy Code Cohort's model amendments) as scheduled for City Council consideration May 12, 2026, with an anticipated effective date of July 1, 2026, but does not confirm the ordinance has actually passed as of the extraction date. Confirm current status with Building Services (303-651-8332) before relying on this for a live project.
• Longmont's Geographic & Climatic Design Criteria are jurisdiction-specific: 30 psf ground snow load, 110 mph nominal/142 mph ultimate wind speed, Seismic Design Category B, 30-inch frost depth, Severe weathering, Slight-to-Moderate termite risk. Cite these directly rather than assuming Denver or statewide Colorado figures — they differ from Denver's ASCE Hazard Tool approach and from Reno's Nevada-specific table.
• Longmont does not fully delegate electrical/plumbing/mechanical trade licensing to the Colorado DORA boards, nor does it fully replicate Denver's own-program model — it uses a hybrid: contractors must hold the underlying Colorado state trade license (Master Electrician/Electrical Contractor, Master Plumber/Plumbing Contractor, or ICC Master Mechanical certificate) AND separately register with the City of Longmont. Electrical registration carries no additional city fee beyond the one-time $25 sales/use-tax charge for new contractors; Plumbing and Mechanical (Class D) registration each carry a distinct $75 city fee.
• Longmont's 'one square' re-roofing rule (since 2012) is stricter than many jurisdictions: any repair/replacement exceeding 100 sq ft (one roofing square) triggers a requirement to replace the ENTIRE roof, not just the damaged plane, and overlay (roofing over existing layers) is never allowed.
• Colorado's statutory Fair Permit Act (SB17-179 / CRS 24-32-3319) caps aggregate city solar PV permit fees at $500 residential / $1,000 commercial — Longmont's Solar PV Systems page confirms this cap applies, informally referencing it as 'House Bill 1199.'
• A homeowner may self-permit as their own general contractor on their own primary residence for building, and specifically for roofing, without holding a Longmont contractor's license — but any subcontracted trade work must still be performed by a contractor licensed to work in Longmont specifically.
• Applications for most Longmont permit types are submitted through the Accela Citizen Access (ACA) portal (aca.longmontcolorado.gov) rather than a walk-in-only or a different e-permits platform — register for an account before applying.
• Longmont's Fee Manual is reissued periodically within a fiscal year (a 2025 edition and a March 24, 2026 edition were both found live) — always confirm you are citing the CURRENT fee manual version, as fee amounts shift between revisions.