Building codes typically update on a three-year cycle, but as the industry moves toward 2026, the pace and scope of changes are accelerating. 

As jurisdictions adopt newer versions of the International Building Code (IBC), International Energy Conservation Code (IECC), and ASHRAE 90.1, specifiers face growing pressure to select envelope systems that do more than simply pass plan review. 

Specifiers will see higher performance expectations for entire wall and roof assemblies, not just individual materials. Insulated metal panels (IMPs) can help meet these evolving energy and fire code requirements when they are selected and documented as complete, tested systems.

This article outlines the most important building code trends impacting IMPs, with a focus on higher energy-efficiency mandates, evolving fire code provisions, and practical strategies for IMP code compliance.

Building Code Compliance Is Becoming More Complex

Recent code cycles tie energy, fire, and envelope performance together, especially for assemblies with foam plastic insulation.

According to the Continuing Education Center, the 2024 edition of the IBC “brings significant updates and new provisions concerning fire safety requirements for foam plastics and exterior wall assemblies containing combustible components.”

These updates reflect a growing emphasis on how exterior wall and roof assemblies behave as systems rather than collections of individual products.

The 2024 IBC adds and clarifies provisions around exterior wall fire performance, NFPA 285 testing, and the authority of building officials under Section 104.

• Exterior wall and roof assemblies are evaluated as systems, not collections of parts.
• NFPA 285 is more explicitly triggered for exterior walls with foam plastics and combustible claddings.
• Code officials have broader discretion to interpret intent and require documentation at the assembly level.

In this environment, IMPs perform best when their tested assemblies, listings, and details clearly match project design and code language.

Energy Codes: Higher Bars, Tighter Margins

Newer editions of the IECC and ASHRAE 90.1 continue to ratchet up minimum envelope performance and emphasize continuous insulation. These standards increasingly reference tested U-factors and integrated air barriers rather than nominal R-values alone.

Continuous Insulation and IMPs

The commercial provisions of IECC and ASHRAE 90.1 favor assemblies that reduce thermal bridging through continuous insulation across the envelope. Factory-insulated IMPs inherently provide a continuous layer of insulation with fewer thermal breaks compared to multi-part wall systems with intermittent insulation and numerous fasteners.​

• Supports prescriptive paths by delivering compliant U-factors and continuous insulation in one component.​
• Improves performance modeling outcomes without excessive wall thickness or complex layer build-ups.

Air Leakage and Assembly Continuity

Both IECC and ASHRAE 90.1 require defined air barriers and treat air leakage control as integral to envelope performance. Because IMPs combine structure, insulation, and metal skins in a single factory-assembled panel, they can simplify continuity at joints and transitions and reduce field-installed layers.

Fire Codes: System-Level Scrutiny for IMPs

As insulation levels increase, the 2024 IBC updates exterior wall provisions to ensure assemblies with foam plastic insulation perform safely under fire exposure. NFPA 285 is reinforced as the primary test standard for vertical and lateral flame propagation in many exterior wall configurations with foam plastics or combustible cladding.​

• Foam plastic insulation in exterior walls must comply with Chapter 26, including NFPA 285, where triggered.​
• Triggers now more clearly include foam plastics, certain claddings, and EIFS-type systems.​
• Tested assemblies, not just individual product flame spread data, are central to approval.​

Properly tested IMP systems, with steel facings and documented foam core performance, can fit well within these requirements, but approvals based on older code language may not automatically transfer into the 2024 cycle.

Quick View: Where Codes Touch IMPs

Specifier Checklist: IMP Fire & Energy Code Readiness

When specifying insulated metal panels for projects breaking ground in 2026 and beyond, the following considerations can help reduce approval risk and streamline permitting:

• Assembly-Level Fire Testing:
  Confirm that the IMP system has documented assembly testing that aligns with current IBC requirements, including applicable NFPA 285 evaluations where required.
• Foam Plastic Insulation Documentation:
  Verify that foam core materials meet fire performance criteria when used within the tested assembly, not just as standalone products.
• Third-Party Certifications and Listings:
  Look for UL, FM, or equivalent certifications that support both fire safety and structural performance claims.
• Clarity in Approved Assemblies:
  Ensure that approved wall and roof assemblies clearly match the proposed design, including facings, thicknesses, fastening methods, and penetrations.
• Jurisdictional Amendments:
  Review local or state amendments that may impose stricter fire safety requirements than the base IBC, especially in urban, coastal, or high-risk regions.
• Authority Having Jurisdiction Engagement:
  Engage the AHJ early when using high-performance envelope systems to confirm the interpretation of compliance paths under Section 104.
• Manufacturer Support:
  Confirm that the IMP manufacturer can provide up-to-date test reports, engineering support, and code documentation during plan review and inspection.

How Green Span Profiles Can Help

Emerging code language around continuous insulation, air barriers, and NFPA 285–tested exterior walls aligns well with properly engineered IMP systems. 

Green Span Profiles offers insulated metal wall and roof panels designed and tested to help meet stringent energy and fire provisions while simplifying documentation for plan review and inspection. 

Specifiers can work with Green Span to review project-specific insulated metal panel building code requirements, confirm applicable tested assemblies, and assemble the documentation needed for smoother approvals in the 2026 cycle and beyond.

Connect with Green Span Profiles to specify insulated metal wall and roof panels designed to meet today’s building codes and adapt to tomorrow’s compliance challenges.