Question 1

What is steel grating?

Accepted Answer

Steel grating is an open-grid metal flooring made of load-bearing bars joined by perpendicular cross bars. It is strong, drains freely, lets light and air pass, is self-cleaning and slip-resistant — used for platforms, walkways, stair treads and drainage covers.

Question 2

What is bar grating?

Accepted Answer

Bar grating is the most common steel grating, named for its rectangular load-bearing bars set on edge. Cross bars lock them into a rigid panel. It is specified by bar size, spacing and panel dimensions and made to project requirements.

Question 3

What is FRP grating?

Accepted Answer

FRP (fibreglass reinforced plastic) grating is moulded or pultruded from glass fibre and resin. It is corrosion-resistant, non-conductive, non-sparking and about a quarter the weight of steel — the choice for chemical, water, marine and electrical areas.

Question 4

What does serrated grating mean?

Accepted Answer

Serrated grating has notched (toothed) tops on the bearing bars to give extra grip underfoot. It is chosen for wet, oily or icy areas where slip resistance matters, at a small cost in surface smoothness.

Question 5

What is the difference between steel grating and expanded metal?

Accepted Answer

Steel grating is built from separate bearing and cross bars and carries much higher loads over longer spans. Expanded metal is a single sheet slit and stretched into a diamond mesh — lighter and cheaper but for light-duty walkways, screens and infill, not heavy platforms.

Question 6

What are the types of steel grating?

Accepted Answer

The main types are welded bar grating (cross bars resistance-welded on — strongest, most economical), press-locked (cross bars pressed in without welding — architectural), swage-locked (cross bars cold-swaged in — common for aluminium) and riveted (high lateral rigidity).

Question 7

What is the difference between welded and press-locked grating?

Accepted Answer

Welded grating is forge-welded at every cross intersection for maximum strength and value. Press-locked grating presses the cross bars into notched bearing bars without welding, giving a cleaner weld-free architectural finish with good rigidity but typically lower load capacity per weight.

Question 8

What is the difference between welded and swage-locked grating?

Accepted Answer

Welded grating fuses cross bars to bearing bars with heat for maximum strength, common in carbon steel. Swage-locked grating presses (swages) cross bars into punched bearing bars cold, with no heat distortion — the usual method for aluminium grating and prefabricated panels.

Question 9

What do W19, W11 and other grating codes mean?

Accepted Answer

The numbers describe spacing: the bearing-bar pitch and cross-bar pitch in a manufacturer or standard code. For example W-19 means bearing bars on about 19 mm-equivalent centres. Always confirm the exact pitch in millimetres or inches with the supplier.

Question 10

How do I select the right grating?

Accepted Answer

Choose by clear span and design load: pick a bearing-bar size whose tabulated capacity exceeds your load at that span, then set the spacing for the surface and drainage you need, and the material (steel or FRP) for the environment. Our load calculator and load tables do the maths.

Question 11

How do I read a grating load table?

Accepted Answer

Find your clear span (column) and your design load (kPa or psf), then pick a bearing bar whose capacity at that span meets or beats the load (row). Check that deflection is within a span/200 guide. See our full load tables for worked values.

Question 12

What size grating do I need?

Accepted Answer

It depends on span and load. As a rule, deeper and thicker bearing bars carry more over longer spans. Send us your span, load and environment and we will recommend a bar size — or size it yourself with our calculator.

Question 13

How much weight can steel grating hold?

Accepted Answer

It depends entirely on bar size, spacing and span. A common 25×3 mm bar at 1 m span carries roughly 14 kPa (about 290 psf) uniform load, while a 65×5 mm bar at the same span carries over 150 kPa. Use a load table or calculator for your exact case.

Question 14

What is the maximum span for steel grating?

Accepted Answer

There is no fixed maximum — it depends on the bearing bar and the load. Deep bars (75–100 mm) can span 2 m or more at moderate loads, while shallow bars are limited to under a metre. Beyond about 2 m, deflection usually governs and a deeper bar or intermediate support is needed.

Question 15

Is FRP grating stronger than steel grating?

Accepted Answer

Per unit weight FRP is very strong, but for a given panel depth steel bar grating carries higher loads. FRP wins on corrosion resistance, light weight and being non-conductive, so it is chosen for chemical, water and marine service while steel handles the heaviest structural loads.

Question 16

When should I choose FRP over steel grating?

Accepted Answer

Choose FRP where corrosion, electrical safety or weight dominate — chemical plants, water treatment, marine, food and electrical areas. Choose steel for the highest structural loads, high temperatures and lowest upfront cost. See our FRP vs steel comparison.

Question 17

Is FRP grating more expensive than steel?

Accepted Answer

FRP usually costs more upfront, but in corrosive service its lifetime cost is lower because it needs no re-coating and lasts 25+ years without corroding. In dry structural use, galvanized steel is the more economical choice.

Question 18

Why is steel grating hot-dip galvanized?

Accepted Answer

Hot-dip galvanizing coats the steel in zinc (typically to ASTM A123) to stop rust. It gives decades of maintenance-free outdoor service and is the standard finish for industrial and marine grating. Painted or bare options exist for indoor or short-life use.

Question 19

What are the disadvantages of galvanized grating?

Accepted Answer

Galvanizing adds cost and lead time, can leave a non-uniform finish, and the zinc layer wears slowly in very abrasive or aggressive chemical environments — where FRP or stainless is preferred. Cut edges should be touched up to keep protection.

Question 20

Can I get custom-made grating?

Accepted Answer

Yes. We are a factory-direct supplier, so grating is made to your specification — bar size, spacing, panel size, banding, serration and finish — rather than fixed stock SKUs. Send a drawing or spec for a fast quote.

Question 21

How much does steel grating cost?

Accepted Answer

Price depends on bar size, spacing, finish, quantity and destination, so grating is quoted per project rather than listed. Factory-direct supply keeps cost competitive — send your spec for a quote.

Question 22

What are the standard sizes of steel grating?

Accepted Answer

Bearing bars commonly run from 20×3 mm up to 100×10 mm, with bar spacing around 19, 30 or 38 mm and cross bars at about 50 or 100 mm. Stock panels are often 1 m × 6 m, but because grating is custom-made, sizes are cut to your project.

Question 23

What standards apply to steel grating?

Accepted Answer

Common references include ANSI/NAAMM MBG 531 (metal bar grating manual) in North America, and material and coating standards such as ASTM A1011/A36 for steel and ASTM A123 for hot-dip galvanizing. Many export markets follow equivalent ISO or national standards.

Question 24

Is steel grating slip resistant?

Accepted Answer

Plain grating is moderately slip resistant because the open surface drains liquids, and serrated grating adds toothed bar tops for extra grip in wet, oily or icy conditions. Stair treads add a serrated or abrasive nosing for safety.

Question 25

How is steel grating installed and fixed?

Accepted Answer

Grating panels sit on supporting beams and are secured with grating clips (saddle clips or G-clips) bolted around the bearing bars, or by welding to the supports. Clips allow removal for access; welding is permanent.

Question 26

What is banding on grating?

Accepted Answer

Banding is a flat bar welded across the cut ends of the bearing bars to close and strengthen a panel edge. It tidies the appearance, protects the cut ends, and keeps the bars aligned, especially on cut-outs and non-rectangular panels.

Question 27

What is stainless steel grating used for?

Accepted Answer

Stainless steel grating (typically 304 or 316) is used where corrosion resistance and hygiene matter but steel-level strength is still needed — food and beverage, pharmaceutical, marine and chemical plants. It costs more than galvanized steel but needs no coating.

Question 28

What is heavy-duty steel grating?

Accepted Answer

Heavy-duty grating uses deep, thick bearing bars (typically 50–100 mm deep) and often closer spacing to carry vehicle, forklift and heavy industrial loads over longer spans. It is specified by the wheel or area load it must support.

Question 29

What is a grating stair tread?

Accepted Answer

A grating stair tread is a single grating step fabricated to stair dimensions, with a serrated or abrasive nosing at the front edge and end plates for bolting to the stringers. It gives a strong, free-draining, slip-resistant step for industrial stairs.

Question 30

What is trench and drainage grating?

Accepted Answer

Trench grating is bar grating cut to cover drainage channels and trenches, letting water through while carrying foot or vehicle loads. It is sized to the channel width and the traffic load, and can be hinged or boltdown for security.

Steel & FRP Grating FAQ

Grating basics

Types & construction

Selection & load

FRP vs steel

Galvanizing, specs & buying

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