A load table has three inputs: span, load and deflection

An FRP grating load table is not a single answer to how much the panel can carry. It tells you how far the panel deflects at mid-span under a given span and load. Every table contains the span between supports, the applied load and the resulting mid-span deflection; ultimate load is listed in a separate column.

Match those three quantities first, then select. Reading only the ultimate load, or only one load figure, is how the wrong panel gets specified.

Linear and uniform load are not interchangeable

Linear load is given in kg/m and treats the load as distributed along a line, such as a pipe crossing the panel, a concentrated foot load or a wheel load. Uniform load is given in kg/m² and spreads the load evenly over the panel, such as a crowd, stored material or a full bed of medium.

The same panel deflects differently under the two cases, so the tables are published separately. Reading a pipe load as uniform underestimates local deflection; reading a crowd load as linear overstates the requirement. Decide how the load actually acts before choosing the table.

Walk through 19*19H30

For moulded 19*19H30, the linear table gives 2.29 mm mid-span deflection at a 600 mm span and 300 kg/m. At 900 mm and the same 300 kg/m, deflection rises to 9.08 mm. The corresponding ultimate loads are 4112 kg/m and 2637 kg/m.

The uniform table gives 2.66 mm at 600 mm and 500 kg/m², and 5.56 mm at 1000 kg/m². Going from 600 mm to 750 mm, deflection at 500 kg/m² rises from 2.66 mm to 5.12 mm, and at 1000 kg/m² from 5.56 mm to 11.0 mm.

Every cell is a mid-span deflection, not a carrying capacity. Span influences deflection more strongly than load: double the load and deflection roughly doubles; increase the span by half and deflection can more than triple.

Ultimate load is not working load

Ultimate load is what the panel can take before failure, the upper bound published in the table. Working load is kept far below it by a safety factor. In most walkway projects, the deflection limit decides the mesh and depth long before the ultimate load is reached.

Treating ultimate load as allowable load is the most common reading error. An ultimate load of 4112 kg/m at a 600 mm span does not mean 4112 kg/m can be placed there permanently; it only marks the failure ceiling, and the working value must be calculated with the project's safety factor and deflection limit.

Set the deflection limit before reading the table

The deflection limit comes from the project specification or the applicable standard. Many walkway projects use about span/100, but that is not a universal rule; crowded areas, trolleys, precision equipment or drainage requirements may demand a stricter limit.

At a 600 mm span and L/100, the limit is 6 mm. The table's 2.29 mm at 300 kg/m linear and 2.66 mm at 500 kg/m² uniform both pass. At 900 mm, L/100 becomes 9 mm, while 300 kg/m linear gives 9.08 mm, just over the limit; at that point, go to a larger mesh, add a support or switch to pultruded grating.

Set the limit first, then read the table. Reversing the order turns selection into finding a justification for a panel already chosen.

Heavy meshes and pultruded grating

When the span or load exceeds the standard mesh range, heavy moulded panels take over. 50*50H50 is rated to a 1200 mm span, with linear ultimate loads of 21727, 11713, 7780 and 5834 kg/m at 300, 600, 900 and 1200 mm.

38*152H38 carries its load bars longitudinally along the span, with a uniform ultimate load of 8418 kg/m² at 1200 mm; it suits short support spacing and heavy loads. Beyond that, pultruded grating along the load-bar direction is usually the better answer. Moulded and pultruded panels carry load differently and cannot be compared by weight alone.

Five steps for reading a table

First, decide whether the load is linear or uniform. Second, use the clear span between supports, not the panel length. Third, read the mid-span deflection at the target load on that row. Fourth, compare it with the project limit. Fifth, if it fails, change the mesh, add a support or move to pultruded grating; do not reach for the ultimate load.

Interpolation between the listed spans and loads is an estimate. When the span, load or support condition falls at the edge of the table, ask the supplier for a calculated value. Support width, continuous spans and lateral restraint also affect the result and cannot be read from a simple table alone.

Send the conditions with the inquiry

Give the span, working load, load type, deflection limit, panel size, support arrangement, medium and temperature. "It has to take foot traffic" or "it has to carry load" leaves the supplier guessing.

For a quick first estimate, use the FRP grating load calculator, then check the result against the published tables.

Mesh, panel depth, resin and surface options are listed in the FRP grating specifications guide; the difference between moulded and pultruded panels is covered on the moulded versus pultruded page.

The short rule

A load table tells you deflection, not how much weight can be placed. Fix the load case and the limit first, find the span row second, and only then choose mesh and depth.