Deck / Covered Patio Permit in Longmont, Colorado
Required for construction of decks, patios, sunrooms, pergolas, and similar structures in Longmont. Classified as an 'Addition' under the City's building permit requirements and reviewed against the 2021 IRC and Longmont's climatic/geographic design criteria (30 psf snow load, 30-inch frost depth for footings).
Verified 2026-07-01 · Source
When you need this permit
- Building permit required for patios, sunrooms, decks, pergolas, swimming pools, and accessory buildings greater than 120 sq ft in area
- Accessory buildings 120 sq ft or less still must meet setback requirements even without a building permit
- Retaining walls over 48 inches require a building permit
- Homeowner may self-permit as own contractor on their own property
Required documents
- Req
Miscellaneous / Residential Remodel-Addition Application (via ACA portal)
Online application through Accela Citizen Access
- Req
Site Plan
Property lines, existing structures, proposed deck/patio footprint, setbacks
- Opt
Accessory Building Guide
City of Longmont's guide covering accessory structure standards (referenced for decks and similar accessory-adjacent structures)
Fee schedule
| Fee type | Amount | Notes |
|---|---|---|
| Building Permit Fee — valuation-based (Primary Fee Schedule) | Assessed on project valuation (gross floor area/scope of work × ICC Building Valuation Data or RS Means Building Construction Cost Data) applied to the Primary Fee Schedule's Building Permit Fee table: $27.00 minimum (valuation $1-$500), scaling up to $6,448.55 for the first $1,000,000 plus $4.20 per additional $1,000 | City of Longmont FY2026 Planning & Development Services Fee Manual (effective 3/24/2026), Building Permit Fees Overview + Primary Fee Schedule (PDF p.6): decks, patios, sunrooms, and pergolas are classified as 'Additions' and are not among the itemized flat-fee 'Other Permits' line items, so they are billed via the published, valuation-based Primary Fee Schedule — the same grounded table used for new construction and residential additions/remodels |
| Plan Review Fee | 50% of the Building Permit Fee | FY2026 Fee Manual, Plan Review Fees table |
Review timeline
~0–0 business days
Typical estimate — confirm current times with the Longmont building department
Inspection process
- 1
Footing
Before concrete pour for structural post footings — must extend below 30-inch frost line
- 2
Framing
Structural framing before decking/cover installed
- 3
Final
Structure complete per approved plans
Tips
- Unlike Reno and Denver, Longmont does not publish a separate flat-rate fee for decks/patios — instead they are billed via the city's published, valuation-based Primary Fee Schedule (the same grounded table used for other additions), plus 50% plan review.
- Deck footings in Longmont must extend below the 30-inch frost depth specified in the city's Geographic & Climatic Design Criteria table.
- Accessory buildings of 120 sq ft or less are exempt from the building permit requirement itself but still must meet zoning setback requirements — check with Planning if in doubt.
Frequently asked questions
- Do I need a permit to build a deck in Longmont?
- Yes. Decks are explicitly listed as an example of an 'Addition' requiring a building permit under the City of Longmont Fee Manual's Work That Requires a Building Permit section.
Sources & verification
Verified against official sources. Last reviewed 2026-07-01.
- City of Longmont — Building Services (Building Inspection Division), Development Services Center — official building department
- City of Longmont FY2026 Planning & Development Services Fee Manual (effective 3/24/2026, PDF)
- 2021 IBC/IRC Geographic Climatic Data Table — City of Longmont (PDF)
Fees, timelines, and adopted codes are researched from each jurisdiction's published records — see how we verify. Requirements change and vary by project, so always confirm the current details with the Longmont building department before you submit. PermitBase is an independent reference and is not affiliated with any government agency.
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