Welded vs Press-Locked Steel Grating

Specify welded steel grating for structural industrial floors, trench covers and mezzanines where shear strength and lowest cost dominate; specify press-locked grating for pedestrian bridges, façades and any deck where the top surface is on show. The two methods share the same bearing-bar logic — the difference is how the cross bars are joined.

Last updated: March 12, 2026

Key takeaways

Welded = resistance weld at every intersection → highest shear, lowest cost, visible weld spots, bar height 20–100 mm. Press-locked = cross bars pressed into notched bearing bars → smooth weld-free top, bar height 20–60 mm, preferred for architectural decks. Default to welded with 30/40 mm pitch for industrial flooring; choose press-locked where appearance and cleanability justify the premium.

How the two gratings are made

The joining method is the single decision that drives every downstream property.

Welded steel grating runs the bearing bars and cross bars through a resistance welding line that fuses every intersection. The result is a rigid panel with the highest shear strength of any grating type and the lowest production cost for typical industrial volumes. You see small weld spots at each crossing — irrelevant on a plant floor, but noticeable on a visitor-facing deck.

Press-locked (swage-locked) grating first cuts a shallow notch into each bearing bar, then presses the cross bars into those notches under hydraulic force so they lock in place. There are no welds and no spots: the top is flat and continuous. That clean surface is easy to walk on, easy to clean, and reads as a finished architectural element rather than a utility product.

Both are built on the same bearing-bar and pitch system, so the load logic on the steel grating specifications page applies to either method — only the joining and the achievable bar range differ.

Load-bearing characteristics compared

Both carry walkway and platform loads well; the difference is in the ceiling, not the floor.

Property Welded steel grating Press-locked grating
Joining method Resistance weld at every intersection Cross bars pressed into notched bearing bars
Top surface Flat bars, visible weld spots Smooth, continuous, weld-free
Shear / load rating Very high — lowest cost High
Bearing bar height range 20 – 100 mm 20 – 60 mm
Best application Platforms, walkways, trench covers, mezzanines Pedestrian bridges, façades, decorative screens

Load capacity is governed by the bearing-bar section and support span, not by the joining method alone. A 40×5 mm bar at 30 mm pitch spans roughly 900–1000 mm between supports for pedestrian loads; halving the span about quadruples the allowable load. See the specifications page for the full decision tree.

Practical rule: for heavy plant platforms and vehicular trench covers, welded construction with 50×5 mm or 60×5 mm bars at 30–40 mm pitch is the robust default. Press-locked is the right call when the deck is visible and the loads are pedestrian or light service.

Where surface finish decides the spec

On an invisible plant floor, finish is a non-issue. On a public deck, it is the whole argument.

Welded grating's weld spots are cosmetic only — they do not affect performance — but on a pedestrian bridge, a transit concourse or a building façade they read as "industrial". Press-locked grating removes that visual cue entirely. The flat, weld-free top also sheds debris and is far easier to pressure-wash, which is why it appears in food-adjacent and clean-room-adjacent service areas where the base material is stainless rather than carbon steel.

Remember that slip resistance is a separate axis. If the visible deck is also wet or inclined, you can still take serrated bearing bars — serration is offered in both welded and press-locked families, so the appearance decision and the slip decision are independent.

Cost comparison and our recommendation

The material price gap is real; the installed-cost gap is usually smaller.

Cost driver Welded Press-locked
Production process High-volume automated welding Notching + hydraulic pressing
Setup / tooling Minimal Higher (die / notch setup)
Unit price position Baseline (lowest) Premium
Where it pays back General industrial floors Visible / architectural decks

Press-locked carries a moderate premium because of notching and pressing setup, but on a visible deck it can remove the need for a separate architectural finish — narrowing the true installed-cost gap. Both are available from the steel grating product page with the same galvanizing and pitch options.

Recommendation: default to welded steel grating with 30/40 mm pitch for any structural or utility deck. Move to press-locked only when the surface is seen by people and the smooth, weld-free look is part of the design intent.

Frequently asked questions

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

Welded steel grating joins the bearing bars and cross bars by resistance welding at every intersection, giving the highest shear strength at the lowest cost for most industrial loads. Press-locked (swage-locked) grating presses the cross bars into pre-cut notches in the bearing bars, producing a smooth, flat top surface with no visible welds. That finish makes press-locked the preferred choice for architectural and pedestrian-facing decks where appearance and cleanability matter more than absolute lowest price.

Is press-locked steel grating weaker than welded steel grating?

Press-locked grating is not weak — it is rated as high strength in its own range, but its mechanical interlock comes from notched bearing bars rather than welds, so the practical bar height range is 20–60 mm versus 20–100 mm for welded. For standard walkway and platform loads on 30 or 40 mm pitch, both perform well. When you need the tallest bars, heaviest sections or vehicular trench covers, welded construction with 50×5 or 60×5 mm bars at 30–40 mm pitch is the safer specification.

Which type of steel grating costs more to supply?

Welded steel grating is the baseline and lowest-cost option because high-volume automated welding needs minimal tooling. Press-locked grating carries a moderate premium from the notching and hydraulic pressing setup, but on visible decks it can remove the need for a separate architectural finish, so the total installed cost difference is often smaller than the material price gap suggests. Choose welded for general industrial floors and press-locked where the surface is on show.

When should I specify serrated bearing bars instead of plain?

Specify serrated (toothed) bearing bars on wet, oily, inclined or outdoor surfaces where slip resistance is critical — stair treads, ramps and wash-down areas are the usual cases. Plain bearing bars are appropriate for dry indoor plant floors and any location where a smooth, easy-to-clean top is preferred. Serration is available in both welded and press-locked families, so the slip decision is independent of the welded-versus-press-locked choice.

Related guides & references

Send us your deck and we will specify it

Tell us the application, span, load and whether the surface is visible. We will confirm welded or press-locked construction and return a quotation, usually within 48 hours.