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Food-grade mezzanines: built for wash-down.

A mezzanine in a food plant does the same structural job as any other — but if it can't be cleaned properly, it becomes a contamination risk instead of usable space. What separates a food-grade platform from a standard one is in the material, the slope, and the details.

// Engineering · 2026-07-15 · 5 min read

Short answer: a food-grade mezzanine uses wash-down-durable materials (stainless, or coated carbon steel), sloped surfaces that drain, and sealed or continuously-welded connections with no crevices or flat ledges to harbour bacteria. It meets the same OBC and CWB structural standards as any mezzanine, detailed to support cleaning rather than obstruct it.

Material: stainless vs coated carbon steel

The wash-down environment drives the material. Stainless steel — 304 for general areas, 316 where chlorides or aggressive sanitation chemicals are in play — is the durable, direct-contact standard. Carbon steel with a food-grade coating (epoxy or similar) is a cost-effective choice for structure away from direct product contact. Most real platforms mix the two: stainless where it matters, coated carbon steel where it doesn't.

Slope: water has to leave

The single biggest difference from a standard mezzanine is that surfaces are designed to drain, not pond. Decks are sloped so wash-down water runs off to a drain point rather than sitting in low spots, and horizontal ledges — the flat top of a beam, an open channel section facing up — are minimised or capped, because anything that collects water collects contamination. It's a geometry problem as much as a material one.

Connections: no crevices

Bolted lap joints and intermittent welds leave gaps and crevices that trap product and resist cleaning. In high-care areas the answer is continuous welds, ground smooth, and hollow sections either sealed or avoided so there's no unreachable interior. The detailing goal is a surface a cleaning crew can actually reach and verify.

Decking choice follows the sanitation plan

In a wet wash-down zone, a solid deck sloped to drain keeps water and debris off whatever is below and can be squeegeed clean. Bar-grate is used where drainage through the deck is actually wanted and nothing sensitive sits beneath. The decking decision here is led by the cleaning plan, not just the load rating.

It's still a mezzanine underneath

All of the above sits on top of a normal structural job — the platform is engineered to its load rating, stamped to the Ontario Building Code, and welded to CWB W47.1. Food-grade design adds requirements; it doesn't replace the structural ones. We coordinate the two so the platform is both sound and sanitary. More on the vertical in food processing.

Frequently asked

What makes a mezzanine "food-grade"?

It's not one thing — it's a set of sanitary-design choices: materials that stand up to wash-down (stainless steel, or carbon steel with a food-grade coating), surfaces that slope so water drains instead of pooling, connections sealed or continuously welded and ground smooth so there are no crevices to harbour bacteria, and no flat ledges collecting debris. The goal is a structure that cleans out completely and doesn't become a contamination source.

Stainless steel or coated carbon steel for a food mezzanine?

Both are used. Stainless (304 for general areas, 316 where chlorides or aggressive wash-down chemicals are present) is the premium, most durable choice and is standard in direct-contact and high-care zones. Carbon steel with a food-grade epoxy or similar coating is a cost-effective option for structural elements away from direct product contact. The zone and the wash-down regime decide which is appropriate.

Should a food-grade mezzanine use bar-grate or solid decking?

It depends on what's below and how it's cleaned. In a wet, wash-down area, a solid deck sloped to drain keeps water and product from falling onto whatever is beneath and lets the surface be squeegeed clean. Bar-grate is used where drainage through the deck is wanted and nothing sensitive sits below. The choice is driven by the sanitation plan, not just the load.

Do food-grade mezzanines have to meet a specific standard?

The structure still meets the Ontario Building Code and is welded to CWB W47.1 like any mezzanine. On top of that, food facilities work to CFIA requirements and sanitary-design principles, so the mezzanine is detailed to support cleaning and inspection rather than obstruct it. We coordinate the structural design with your food-safety and sanitation requirements.