City of Aurora Climatic Design Criteria for Garage Door Specifications

Aurora is the third-largest city in Colorado and the second-largest city in the Denver metro area. It sits in Arapahoe County at about 5,400 feet elevation, just east of Denver. Aurora publishes its own climatic design criteria in its municipal code. These values drive every structural garage door decision in the city.

What this source says

City of Aurora Municipal Code Section 22-186 establishes the climatic and geographic design criteria applicable to all construction within Aurora's city limits. The section states:

Ground snow load: 40 psf. Ultimate design wind speed (Vult): 115 mph. Wind exposure category: C. Frost depth: 36 inches. Seismic Design Category: B. Ice barrier underlayment required: No.

Aurora's ground snow load of 40 psf is slightly lower than Denver's 43 psf. Denver updated its snow load from 35 psf to 43 psf in the 2025 code cycle. Aurora's 40 psf reflects local meteorological data for the Arapahoe County area. Both values are higher than the 30 to 35 psf values that were commonly used in the region before ASCE 7-22 conversions were applied.

Wind design values (115 mph, Exposure C) match the broader Front Range standard. Exposure C applies because Aurora is in relatively open terrain with few major windbreaks, particularly on its eastern and southeastern sides.

When it applies

Any Aurora building permit. Section 22-186 values apply to all projects requiring a permit in Aurora. For garage door projects, the values drive structural header design and wind label requirements.

Garage door wind rating. Under IRC R609.4, a garage door must be tested per ANSI/DASMA 108 at a design pressure that meets or exceeds the required pressure for the location. For a 16x7 door in Aurora at 115 mph Exposure C, the required design pressure is approximately 20 to 22 psf. The door's permanent wind label must show a tested rating at or above that level.

Header design above the opening. For any permitted structural work above a garage door (new opening, enlarged opening, or structural renovation), the header must be designed for a roof snow load derived from the 40 psf ground snow load. This is slightly less demanding than Denver's 43 psf but still requires a properly engineered header for typical garage openings.

Frost depth. Any anchor, footing, or buried element at the garage slab edge must go below 36 inches in Aurora to avoid frost heave. This is the same frost depth as Denver.

What this means for you

Aurora homeowners replacing a garage door. The new door must carry a wind label showing it was tested at 115 mph Exposure C or equivalent design pressure. Most standard residential doors from major manufacturers meet this requirement.

Aurora homeowners adding a new garage opening or widening an existing one. A structural permit is required. The engineer uses 40 psf ground snow load and 115 mph Vult Exposure C. Do not use Denver's 43 psf values for an Aurora project.

Contractors working in both Denver and Aurora. The snow load values differ: 43 psf for Denver, 40 psf for Aurora. Use the correct value for the jurisdiction. Plan reviewer catches this.

Adjacent Arapahoe County unincorporated areas. Areas outside Aurora city limits in Arapahoe County follow different criteria. Confirm jurisdiction and applicable codes with Arapahoe County before starting a project at an address that may straddle the city boundary.

G Brothers serves Aurora and can confirm the applicable Section 22-186 design criteria for your project and supply doors rated to meet them.

Full text and source

Aurora Municipal Code Section 22-186 is at https://aurora.municipal.codes/Code/22-186.

Aurora Municipal Code Section 22-186 applies only within Aurora city limits. Adjacent communities in Arapahoe County (Centennial, Englewood, Sheridan) have their own adopted codes and design criteria. Confirm the applicable jurisdiction for any project near Aurora's borders.

Want to put numbers to this? Use the interactive roof snow load calculator below, or open the full roof snow load calculator with examples and notes.