Roofing work in Longmont, Colorado by Peak to Peak Roofing

Longmont Roofing Codes: Permits, Inspections, and Requirements

Adopted building and energy codes, permit rules, and roofing requirements for Longmont, Boulder County. Rows below reflect our reading of the jurisdiction's own published sources, linked at the bottom of the page.

Last checked September 2, 2026Compiled from published Boulder County and city pages

Building department

Inspection line

Permit line

Official department

Longmont roofing code requirements

Longmont roofing code reference

Current building code

What this jurisdiction requires: 2024 IBC and 2024 IRC

Current energy code

What this jurisdiction requires: Metro Cohort Model Code, based on the 2024 IECC

Building permit required

What this jurisdiction requires: Yes

Plans to update the code

What this jurisdiction requires: Yes, late 2018

Minimum wind speed rating for asphalt shingles

What this jurisdiction requires: 110 MPH sustained wind/130 MPH 3 second gusts

ASTM standard for wind rating

What this jurisdiction requires: ASTM D3161 Class F, D7158 Class G & H

Requires a manufacturer wind warranty

What this jurisdiction requires: Yes

Inspectors carry ladders for the final

What this jurisdiction requires: Yes, with one story access

Requires midroof (in progress) inspection

What this jurisdiction requires: Yes, for commercial before dry-in

Maximum layers of asphalt shingles permitted

What this jurisdiction requires: Only 1 layer is permitted

Maximum layers of flat roof material permitted

What this jurisdiction requires: Only 1 layer permitted

Requires solid sheeting over spaced decking

What this jurisdiction requires: Yes

Requires drip edge

What this jurisdiction requires: Yes

Minimum drip edge size

What this jurisdiction requires: 2 x 3

Requires rake / gable metal edging

What this jurisdiction requires: No

Self adhering underlayment (ice and water shield)

What this jurisdiction requires: No

Underlayment required 2:12 up to 4:12

What this jurisdiction requires: A double layer of underlayment required

Underlayment required 4:12 and above

What this jurisdiction requires: One layer of minimum Type 15 required

Type of valleys allowed

What this jurisdiction requires: Both

Valley material required for closed valleys

What this jurisdiction requires: Either

Valley material required for open valleys

What this jurisdiction requires: Either

Kick-out required on step flashing

What this jurisdiction requires: Yes

Requires ventilation to meet code

What this jurisdiction requires: Yes

Requirement	What this jurisdiction requires
Current building code	2024 IBC and 2024 IRC
Current energy code	Metro Cohort Model Code, based on the 2024 IECC
Building permit required	Yes
Plans to update the code	Yes, late 2018
Minimum wind speed rating for asphalt shingles	110 MPH sustained wind/130 MPH 3 second gusts
ASTM standard for wind rating	ASTM D3161 Class F, D7158 Class G & H
Requires a manufacturer wind warranty	Yes
Inspectors carry ladders for the final	Yes, with one story access
Requires midroof (in progress) inspection	Yes, for commercial before dry-in
Maximum layers of asphalt shingles permitted	Only 1 layer is permitted
Maximum layers of flat roof material permitted	Only 1 layer permitted
Requires solid sheeting over spaced decking	Yes
Requires drip edge	Yes
Minimum drip edge size	2 x 3
Requires rake / gable metal edging	No
Self adhering underlayment (ice and water shield)	No
Underlayment required 2:12 up to 4:12	A double layer of underlayment required
Underlayment required 4:12 and above	One layer of minimum Type 15 required
Type of valleys allowed	Both
Valley material required for closed valleys	Either
Valley material required for open valleys	Either
Kick-out required on step flashing	Yes
Requires ventilation to meet code	Yes

Last checked September 2, 2026. This reflects published sources at that date, not an official ruling. Code adoptions change, so confirm with the Longmont building department before you pull a permit.

What Longmont requires, in plain language

Longmont builds to the 2024 IBC and 2024 IRC. That edition, not the newest code published nationally, is the rulebook an inspector in Boulder County holds your roof to. Energy work on the same permit follows the Metro Cohort Model Code, based on the 2024 IECC. Update status: Yes, late 2018

Layer limit in Longmont: Only 1 layer is permitted. This is the line item that moves a bid the most. If your existing roof is already at the limit, the deck gets stripped before new material goes down, and the labor plus dump fees belong in the written price. Flat roof sections are capped at Only 1 layer permitted.

Wind is what Longmont tests shingles against. Shingles need a 110 MPH sustained wind/130 MPH 3 second gusts rating. Rating is proven under ASTM D3161 Class F, D7158 Class G & H. Manufacturer wind warranty: Yes.

Underlayment and edge metal are where roofs fail inspection. Ice and water shield: No. On 2:12 to 4:12 slopes: A double layer of underlayment required. On 4:12 and steeper: One layer of minimum Type 15 required. Drip edge: Yes. Minimum drip edge size 2 x 3.

Longmont has adopted the 2024 International Codes, the Metro Cohort Model Code, and the Colorado Wildfire Resiliency Code, effective July 1, 2026.

Installation details above come from our building department field survey for Longmont, last updated 8/22/18. Code editions and contacts are refreshed from the department directly. Always confirm the details on your permit before work starts, since departments amend requirements on their own schedule.

Code compliant roof installation near Longmont, Colorado

Sources

https://longmontcolorado.gov/building-inspection/building-codes/

These links go straight to the jurisdiction, so you always have the real-time source. Adoptions and amendments change on their schedule, not ours. Always confirm before permitting.

Keep going

Roof Replacement Roof Inspection Roof Leak Repair Insurance Claims

Nearby jurisdictions

Bennett Berthoud Boulder Brighton Broomfield Commerce City

Last checked September 2, 2026. This is our best read of published sources, not an official ruling. Confirm with the Longmont building department before you pull a permit.