Identify which exterior walls the design says rely on an NFPA 285 tested assembly, then compare every layer on the wall types, sections, and specifications with that assembly’s documentation. AI can flag substitutions and gaps; the architect and authority decide whether the assembly is acceptable.
What does NFPA 285 cover?
NFPA 285 is the Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Wall Assemblies Containing Combustible Components. NFPA describes a test method for determining the fire propagation characteristics of exterior wall assemblies and panels used as components of curtain wall assemblies constructed using or incorporating combustible materials or components.
NFPA’s official NFPA 285 page identifies the 2025 edition as current when checked on October 1, 2026. Confirm the edition, local amendments, and project scope that actually govern the work. The publisher’s newest edition does not establish local adoption.
The adopted building code decides when an exterior wall must be tested to NFPA 285; the standard itself is the test method. Record which walls the code summary says need it and which tested assembly or engineering judgment each relies on. Do not treat a single product data sheet as evidence for a whole wall.
Bring the wall types and the assembly evidence
Collect the code summary, exterior wall types, wall sections, elevations, window and opening head and sill details, and the specifications for insulation, air and water barriers, sheathing, cladding, and panels. Add the tested assembly reports or engineering judgments the design cites, if you have them.
List every layer from the interior finish to the exterior cladding for each wall type. Substitutions during design development or submittals often change a layer without updating the cited assembly.
Match each wall layer to the cited assembly
| Review question | Sources to compare | Decision to record |
|---|---|---|
| Walls requiring evaluation | Code summary, wall types, elevations | Confirm which wall types the design says rely on a tested assembly. |
| Layer-by-layer match | Wall sections, specifications, cited assembly documentation | Identify layers that differ from the cited assembly. |
| Insulation and barriers | Insulation and air barrier specifications, wall types | Check product types named in the specification against the drawings. |
| Cladding and panels | Metal panel or cladding specification, elevations | Trace each cladding product to the wall types where it is used. |
| Openings and edges | Window details, head and jamb details, floor edges | Ask the architect how the cited assembly addresses openings shown. |
| Substitutions | Submittals, addenda, product data | Flag product substitutions that were not reconciled with the assembly. |
The metal wall panel guide, insulation guide, and air barrier guide cover the specification sections whose products make up the wall.
Example: an insulation substitution breaks the cited assembly
Hypothetical example. An addendum changes the exterior continuous insulation to a different product type, while the wall types still cite the original tested assembly and the code summary is unchanged.
The addendum replaces the continuous insulation in this wall type, and the wall type still cites a tested assembly based on the earlier product. Please confirm whether the cited assembly or an engineering evaluation covers the revised layer.
The architect confirms the assembly basis with the manufacturer’s documentation or a new evaluation and updates the wall types and specifications. The conflict is a question about evidence, not a fire test result.
Review exterior wall assemblies with Groundbook
Upload the current project PDFs and relevant specifications to Groundbook. Identify the governing issues and add the applicable NFPA 285 reference from a copy you are licensed to use, where the license permits uploading it. State the edition, amendments, review area, and known exclusions in your instructions.
For each exterior wall type that the code summary says relies on an NFPA 285 tested assembly, compare every layer on the wall types, sections, and specifications with the supplied assembly documentation. Flag substitutions, missing layers, and inconsistent product types. Cite each source.
Groundbook links each potential finding to the wall type, section, or specification article involved. Verify the wall type and revision, and keep missing assembly evidence separate from conflicts between drawings.
Document review does not test an assembly, interpret test results, issue an engineering judgment, or approve a wall. Those remain with the architect, the manufacturer’s qualified evaluators, and the authority having jurisdiction.