Design & specification

Grating Design and Specification Center

A usable grating specification connects the operating environment and load case to a defined panel, support and documentation package.

Decision first

Start with duty, span, support and exposure. Product type comes after those inputs—not before them.

Guide index

Span and bearing directionTranslate the support plan into the correct panel orientation.Read guide →Load and deflection basicsSeparate uniform, concentrated and wheel loads.Read guide →RFQ specification checklistSend the inputs needed for a comparable quotation.Read guide →

Four decisions control the specification

The first decision is what the surface must do: pedestrian access, drainage, process platform, stair tread or wheel-load cover. Next establish the actual clear span and support condition. Then define the governing load cases and serviceability limit. Finally choose a material and finish compatible with the environment.

Duty and access
Clear span and support
Load and deflection criteria
Material, finish and documentation

Use published data correctly

A manufacturer load table applies only to its stated bearing-bar section, pitch, material, span definition, support assumptions and load type. NAAMM publishes separate resources for standard metal bar grating, heavy-duty grating and engineering design. The project engineer remains responsible for the governing design basis and acceptance criteria.

Primary references

Checked 2026-09-03. Verify the edition accepted by your project before use.