1. Governing Roofing Code in Utah
Utah roofing requirements are part of the broader Utah State Construction Code. Roofing standards are mainly based on the
International Residential Code (IRC) and the International Building Code (IBC), as adopted and amended by the State of Utah.
The primary roofing-related code sources include:
- Utah State Residential Code (based on 2021 IRC) – Chapter 9: Roof Assemblies
- Utah State Building Code (2021 IBC, amended)
- Utah State Construction and Fire Codes Act (Title 15A)
These codes apply statewide, though local jurisdictions may enforce additional amendments or requirements.
2. Core Roofing Code Requirements
A. Roof Assembly Definition
A roof assembly may include the following components:
- Roof covering
- Roof deck or sheathing
- Underlayment
- Insulation and vapor barriers, where applicable
B. Roof Coverings & Approved Materials
Salt Lake City permits several approved roofing materials, including:
- Asphalt shingles
- Metal roofing
- Clay and concrete tile
- Wood shingles and shakes (where allowed)
- Membrane systems such as TPO and EPDM
Roofing materials must be properly listed, tested, and installed according to manufacturer instructions and required fire ratings.
C. Fire Classification
Roof coverings may carry one of the following fire ratings:
- Class A – highest level of fire resistance
- Class B
- Class C
In some Utah areas, especially wildfire-prone or dense residential zones, higher fire-rated roofing materials may be required.
D. Roof Slope Requirements
Roof slope requirements depend on the roofing material used. For example, asphalt shingles generally require a minimum slope,
while low-slope roofs often require membrane or built-up roofing systems.
E. Underlayment & Ice Barrier
Utah commonly requires:
- Underlayment beneath roof coverings
- Ice barrier protection in areas susceptible to snow and ice buildup
Ice barriers are especially important in Utah climates and typically must extend from the eaves inward to protect against ice dam damage.
F. Roof Decking / Sheathing
Roof decking must be structurally sound and typically consists of plywood or OSB. In seismic regions, additional structural requirements may apply.
G. Flashing Requirements
Flashing is required at vulnerable transition areas such as:
- Roof penetrations
- Valleys
- Chimneys
- Roof-to-wall intersections
Flashing must be corrosion-resistant and installed to prevent water intrusion.
H. Ventilation
Roof and attic ventilation is required to reduce moisture buildup and prolong roof life. Standard code ratios such as 1:150 or 1:300 may apply depending on design.
I. Drainage
Roofs must be designed to shed water properly. Low-slope or flat roofs must have positive drainage systems to prevent ponding water.
3. Reroofing & Replacement Rules
Reroofing code generally restricts adding a new roof over existing layers in certain situations, such as:
- When the roof deck is damaged
- When there are already two or more existing roof layers
- When the existing roofing material is not suitable for overlay
In these cases, a full tear-off and replacement may be required.
4. Additional Specific Roofing Considerations
Wildland-Urban Interface (WUI) Areas
Some communities have wildfire-related roofing requirements that may require more fire-resistant materials and improved installation standards.
Energy Code Compliance
Salt Lake City also enforces energy code standards, which may affect roof insulation, ventilation, and overall roofing assembly performance.
Zoning Roofing Standards
A Certificate of Appropriateness is required prior to permit issuance if the structure is located within a local historic district.
5. Local Enforcement
Building Services is responsible for permits, plan review, and inspections.
We also enforce local amendments related to:
- Fire zones
- Snow load conditions
- Permit requirements
- Inspection procedures
6. Permits & Inspections
Roof replacement or reroofing work may require permits and inspections depending on the scope of work and local jurisdiction.
Permits are typically issued within 1-2 days after application.
Typical inspections may include:
- Deck or sheathing inspection
- Ice barrier or underlayment inspection
- Final roofing inspection
Key Takeaways
- Utah roofing code is primarily based on the 2021 IRC Chapter 9 and related Utah amendments.
- Major requirements include fire-rated materials, underlayment, ice barriers, proper ventilation, and drainage.
- Reroofing is limited when multiple roof layers or damaged decking are present.
- A permit is required.