Mesh Decks vs Board on Support Bars: Fire, Hygiene and Pallet Flow

Why This Decision Matters More Than Most People Think

Choosing between mesh decks and board on support bars often gets treated as a simple cost decision. In reality, it impacts:

• Fire performance and insurance conversations

• Hygiene and audit outcomes

• How safely and smoothly pallets move through your racking

For a warehouse CEO, owner or manager, the “cheap and cheerful” option can quietly increase risk, especially in sprinklered or hygiene-critical facilities. This article unpacks mesh decks vs board on support bars specifically through the lenses of fire, hygiene and pallet flow, so you can make a decision that stands up to auditors, insurers and day-to-day operations.

What Are We Actually Comparing?

Before we dive into detail, let’s define the two options:

Mesh decks

Steel wire panels with built-in support channels that drop straight onto pallet racking beams. They create a ventilated, load-bearing platform for pallets, cartons and irregular items.

Australian suppliers commonly rate mesh decks at 500–1500 kg UDL per deck, with galvanised finishes, 50 × 100 mm mesh, and 3–5 integrated support channels.

Board on support bars

• Loose boards (usually particleboard, MDF or plywood)

• Laid over multiple pallet support bars that run left-to-right between beams

The support bars carry the load into the beams; the board spreads the load and creates a solid surface. It’s familiar and inexpensive, but behaves very differently in fire and hygiene-sensitive environments.

Better Storage Systems supplies both racking accessories – including mesh decks and pallet supports – and can design either option into an engineered pallet racking solution.

1. Fire Performance: Why Insurers Prefer Open Decks

How mesh decks behave in a fire

Open mesh decks allow:

• Sprinkler water to pass through all levels

• Heat and smoke to travel upward, improving sprinkler activation

• Limited fuel load – galvanised steel doesn’t contribute to the fire

Australian suppliers routinely promote mesh decks as being more compatible with AS 2118 automatic fire sprinkler requirements and insurance expectations, because they don’t block water flow in the way solid decking can.

Mesh decking is also marketed as non-flammable or fire-resistant, and many products are certified to relevant strength and fire performance standards (e.g. ANSI MH26.2) in addition to compliance with AS 4084 racking requirements.

How board on support bars behaves in a fire

Timber or particleboard brings several downsides:

• Adds fuel to the fire load (especially chipboard and MDF)

• Blocks sprinkler discharge to lower levels

• Can char, delaminate or collapse when exposed to heat, potentially dropping product and changing how the fire develops

Several Australian storage suppliers explicitly position mesh decking as “a great alternative to boards” because of improved compliance with fire sprinkler requirements and fire codes.

What this means in practice

For a typical sprinklered pallet racking warehouse, many fire engineers and insurers will strongly prefer open, non-combustible decking such as mesh over solid boards. In some risk profiles (e.g. high hazard commodities or dense storage), solid decks may even be restricted or rejected.

Key takeaways for decision-makers:

• Always confirm your decking choice with your fire engineer, insurer and local fire authority, not just your racking supplier.

• If your facility is or will be sprinklered, mesh decks are usually the safer and more compliant starting point.

• If you already have board decking, a racking safety audit and repair can help identify where it’s increasing fire risk and what upgrade path is sensible.

2. Hygiene & Housekeeping: Dust, Liquids and Pests

In food, FMCG, pharma and cold storage, hygiene is non-negotiable – and your choice of decking either helps or hinders your cleaning regime.

Mesh decks: designed to stay cleaner

Mesh decks are widely promoted as:

• Not absorbing liquids or humidity – they’re steel, not timber

• Allowing dust and debris to fall to the floor, where it can be captured in routine sweeping

• Minimising hiding places for pests, mould and moisture

• Suitable for coolrooms and freezers, where swelling or warping of boards is a real issue

Because there’s no continuous solid surface, spills are easier to see, and you can reach product and structure from multiple angles during cleaning.

Board on support bars: hidden grime and long-term hygiene risk

Solid boards:

• Trap dust and debris on the top surface and in gaps along the edges

• Can absorb spills, oils and moisture, leading to staining, odours and potential mould growth

• Are attractive to pests if food products are stored nearby

• Can warp or delaminate in damp or cold environments, making cleaning even harder

From an auditor’s perspective, solid boards are often a hygiene red flag in high-risk industries, especially when combined with infrequent racking inspections.

Where hygiene is critical

If you operate in:

• Food and beverage

• Pharmaceuticals or healthcare

• Cold storage or temperature-controlled logistics

• High-standard retail and FMCG

…then mesh decks align much more naturally with your HACCP, BRCGS or customer audit requirements than timber boards.

A good rule of thumb: if your QA team talks about microbiological risk and cleaning validation, start with mesh and only use boards where explicitly risk-assessed.

3. Pallet Flow and Day-to-Day Handling

“Pallet flow” here means both everyday pallet handling on selective racks and, in some sites, true pallet live / gravity flow systems.

Pallet stability on the rack

Mesh decks:

• Support pallets even when bottom boards are damaged or missing

• Catch fallen cartons if a pallet fails, reducing the chance of product dropping between beams

• Improve visibility through the level for forklift drivers, reducing the “dark canyon” effect at height

Board on support bars:

• Provide a completely solid surface – handy where you routinely store non-palletised items or very small cartons

• But if boards sag or break over time, they can create high spots, low spots or even holes, all of which increase the risk of pallets catching or tipping

In both cases, the racking still needs to be engineered for your unit load, and your forklifts must be matched to frame depth, clearances and bay loads – that doesn’t change. But mesh tends to fail gradually and visibly (bending, rust) whereas boards can fail suddenly when overloaded or degraded.

Pallet live and gravity systems

In true pallet flow (pallet live) racking, pallets sit on rollers or wheel beds, not directly on decks. Solid boards are almost never appropriate inside a gravity lane because they:

• Interfere with the designed flow path

• Add uncontrolled friction and fire load

Where mesh does appear in a pallet live installation is at:

• Pick faces or replenishment levels adjacent to flow lanes

• Safety or catch decks under lanes in certain designs

If you’re considering pallet live storage, this is a full engineered system design, not a DIY add-on. Engage the design & quote team to get the rack structure, lanes and any auxiliary mesh decking designed as a package.

4. Structural Capacity and Durability

From a structural perspective, both options must be selected against the beam capacity, bay load and frame capacity of your racking (per AS 4084).

Mesh decks

• Commonly rated at 1000 kg UDL per deck, sometimes higher, depending on size and number of support channels

• Galvanised finish provides long-term protection against rust in normal warehouse environments

• Do not sag, rot or delaminate, even in coolrooms or mildly damp conditions

Board on support bars

• Capacity depends heavily on:

  • Board thickness and type

  • Number and spacing of support bars

  • Exposure to moisture and impact over time

• Boards can lose capacity as they absorb moisture, crack, chip or delaminate

• Damaged boards are often quietly replaced like-for-like, without checking the original engineered rating

In other words, mesh decks offer a more stable, predictable capacity over the life of the rack, whereas board systems tend to drift if they’re not strictly controlled and inspected.

5. When Board on Support Bars Might Still Make Sense

Despite the drawbacks, there are scenarios where boards remain a reasonable choice – provided risk is understood and managed.

They can suit:

• Light-duty, hand-loaded storage (e.g. spare parts, packaging supplies) where fire and hygiene risk is low

• Non-sprinklered sheds storing non-combustible goods, subject to confirmation with your fire engineer and insurer

• Short-term or temporary fitouts with low utilisation, where budget is extremely constrained

If you go down this path, make sure:

• The system is engineered and documented just like any other pallet racking configuration

• Board type, thickness and number of support bars are specified – not left to chance

• Load signs clearly reflect the reduced capacity and any restrictions (e.g. no pallets, hand-loaded cartons only)

• The system is included in your routine pallet racking inspections, with clear criteria for board replacement

A pallet racking safety audit and repair programme is the easiest way to put those controls in place.

6. Decision Guide: Mesh Decks vs Board on Support Bars

Use this as a quick reference when you’re reviewing a quote or redesigning a zone:

Choose mesh decks if:

• The warehouse is sprinklered or may be in future

• You store food, FMCG, pharmaceuticals or personal care

• You operate cold storage or freezers

• Pallet quality varies and you want a safety net under broken pallets

• You want a durable, low-maintenance platform with predictable capacity

Consider board on support bars only if:

• You’ve confirmed acceptability with your fire engineer/insurer

• Hygiene requirements are modest and audited risk is low

• Loads are light, predominantly hand-loaded and well controlled

• You’re prepared to manage a tighter inspection and replacement regime

In many modern Australian warehouses, especially those chasing AS 4084 compliance and robust insurance outcomes, the question isn’t “Should we upgrade to mesh?” – it’s “Where, if anywhere, is board still acceptable?”

How Better Storage Systems Can Help You Decide

Because Better Storage Systems designs, supplies and installs complete pallet racking systems and racking accessories – not just individual parts – the team can look at your decking choice in context:

• Fire engineering and insurance expectations

• Product mix, hygiene requirements and audit standards

• Existing racking capacities and pallet racking safety obligations

Typical support includes:

• Design & quote for new or upgraded racking, including the right mix of mesh decks, pallet supports and protectors

• On-site inspections to identify high-risk board decking and recommend practical upgrade paths

• Staged retrofit plans so you can move to mesh over time, starting with your highest-risk aisles and product zones

If you’re unsure how your current decking would stand up to a serious fire, a food safety audit or an insurance review, that’s a strong signal to revisit the mesh-versus-board decision now – not after an incident.