Mezzanine floor load capacity in Singapore is settled in kN per square metre before any steel is ordered. From 1 October 2026, BCA and URA make CORENET X mandatory for all new projects, turning that design load into a model parameter rather than a drawing note. This blog walks you through load values, deck choices, grid arithmetic and the load notice Singapore law requires, starting with platform deck specifications.

What load should a mezzanine floor in Singapore be designed for?

Storage areas are designed to 7.5 kN/m2, and that is the only one of the three commonly quoted figures that comes from the code. Under EN 1991-1-1 Table 6.4, Category E1 covers areas susceptible to accumulation of goods including access areas, with a characteristic uniformly distributed load of 7.5 kN/m2 and a concentrated load of 7.0 kN. The other two numbers you see on quotations are conventions. A 2.5 kN/m2 mezzanine sits inside the Category B office range of 2.0 to 3.0 kN/m2, which is a range the National Annex or the project fixes rather than a single code value. A 5.0 kN/m2 mezzanine appears nowhere in Table 6.4 at all. It is a commercial midpoint that suppliers offer for light storage, and it is perfectly legitimate as a specification, provided everyone knows it is a specification. Where this breaks down is retrofit use. A picking mezzanine specified at 2.5 kN/m2 for cartons and one operator per bay is a different structure from a 7.5 kN/m2 platform holding palletised stock, and the two look identical from the floor below. The code also tells you not to stop at the table. For storage areas, EN 1991-1-1 directs that characteristic vertical loads be derived by “taking into account the density and the upper design values for stacking heights”. Design to what you will actually stack, not to a round number that fits the budget.

What is the difference between UDL and point load, and why does both matter?

The uniformly distributed load sets the beam and column sizes. The concentrated load checks whether a single heavy item punches the deck between beams. Both have to pass, and a platform can satisfy one while failing the other. Deck type decides which one bites first. A 38mm chipboard deck spanning 1.2m between secondary beams handles 7.5 kN/m2 spread across the bay and fails under a 7.0 kN wheel or leg landing on one point. Chequered plate and grating behave the opposite way, carrying local point loads well and needing more secondary steel to meet the same UDL. The important qualification is that the 7.0 kN table figure does not cover racking. EN 1991-1-1 states that for concentrated loads from storage racks or lifting equipment, the concentrated load should be determined for the individual case. Your Professional Engineer works out the actual leg load from the rack configuration rather than reading it off a table. That distinction is why a mezzanine load rating and a racking beam rating are two different numbers. Our guide to rack beam load ratings covers the second one.

How does the deck type change the load capacity?

Deck choice does not change the imposed load. It changes the permanent load the beams and columns carry underneath it, and the range between deck types is wider than most buyers expect. Run the arithmetic from material density. A 38mm high density chipboard deck at roughly 750 kg/m3 weighs about 28 kg/m2, or 0.28 kN/m2. A 6mm steel chequered plate at 7,850 kg/m3 weighs 47 kg/m2, or 0.46 kN/m2. Open steel grating lands near 0.29 kN/m2. A composite deck with 50mm of concrete topping runs around 1.3 kN/m2, and a 150mm hollowcore precast plank reaches 2.45 kN/m2. Add those to a 7.5 kN/m2 imposed load and the totals separate. Chipboard gives roughly 7.8 kN/m2 through the frame. Precast planking gives 9.95 kN/m2, about 28% more load into the same columns, base plates and slab. Each deck earns its weight somewhere. Precast and composite give you fire resistance and a hard wearing surface that takes pallet truck traffic. Grating lets sprinkler discharge and light through, which matters under a deck. Chipboard is the cheapest and the one most often specified without anyone asking what will drive across it. We specify chequered plate as the default for pallet handling zones and grating where the deck sits under existing sprinklers. Chipboard belongs on carton picking levels with hand trolleys, and nowhere else.

How is the column grid decided?

The grid is set by what runs underneath, then adjusted until the beam depth stops eating the clear height below. Wider spans need deeper primary beams, and every extra 100mm of beam depth comes off the headroom on the level beneath. Load reaches the ground in stages. The deck spans onto secondary beams, secondary beams span onto primary beams, primary beams land on columns, and columns deliver everything to base plates on the slab. Shorten the secondary beam spacing and you can use a lighter deck. Widen the column grid and both beam layers get deeper and heavier. The tributary area arithmetic is worth doing before you accept a layout. A 6m by 6m grid gives each interior column a 36m2 tributary area. At 7.5 kN/m2 imposed plus roughly 0.5 kN/m2 of deck and framing, that column carries about 288 kN unfactored. Halve the grid to 3m by 3m and the same column carries 72 kN. That factor of four is the whole argument. Tight grids give small columns, shallow beams and more obstructions on the floor. Wide grids give clear space and heavy steel. The multi level design factors guide sets out how the storage layout interacts with the grid, and the forklift operating widths note gives the aisle dimensions that constrain it.

What deflection limit should you specify?

Span over 360 is the limit most Singapore mezzanine specifications use, and it is a specification choice rather than a code requirement. The Eurocodes leave vertical deflection limits to the National Annex or to agreement on the project, which means the number lands in your contract only if someone puts it there. Deflection is a serviceability issue, not a strength one. A deck that meets 7.5 kN/m2 at ultimate limit state and deflects 30mm at midspan is structurally adequate and feels alarming underfoot. On a 6m span, span over 360 caps that at 16.7mm. On a 3m secondary beam span it caps at 8.3mm. Ask for the limit in writing and ask which load case it applies to. Deflection under imposed load alone and deflection under total load give different beam sizes, and a quotation that says only “designed to Eurocode” has not answered the question. Worth noting: rack supported platforms carry their own serviceability rules. SS EN 15512 sets deflection limits and serviceability checks specifically for rack supported floors, which the PE applies alongside the general steel design.

How does forklift traffic change the numbers?

Forklifts are treated as concentrated loads acting together with the distributed load, not instead of it, and EN 1991-1-1 classifies them into six classes by net weight, dimensions and hoisting capacity. A deck rated for static storage is not automatically rated for a truck driving on it. Dynamic effects come on top. The code applies a dynamic factor to forklift actions, so the wheel load your PE designs for exceeds the static axle load. This is the single most common gap we see between what a mezzanine was designed for and what the operation later puts on it. The practical rule is to decide the access method before the design load. A mezzanine served by a pallet gate and a forklift working from the floor below carries a concentrated edge load at the gate position and nothing else from the truck. A mezzanine that a stacker or pallet truck actually drives onto is a different design and usually a different deck. Put the equipment list in the brief. Model, laden weight, wheel configuration, and where it will operate, because the PE cannot infer any of that from a floor area.

What does the load do to your existing slab?

Everything the platform carries arrives at the slab through base plates, and bearing pressure at those points is what the existing floor has to survive. The mezzanine can be designed to any figure you like. The slab underneath it cannot be redesigned. Take the 6m grid column carrying 288 kN. Spread across a 400mm by 400mm base plate, that is 1.8 N/mm2 on the slab surface. Cut the plate to 300mm by 300mm and the same load becomes 3.2 N/mm2. The column has not changed. The pressure has nearly doubled. Three things decide whether that works: the slab thickness and reinforcement, the subgrade beneath it, and the position of the base plate relative to construction joints and existing pits. Base plates landing on or near a joint are a common cause of redesign after the site survey, which is one reason the site survey checklist matters before drawings start. The binding number is usually the landlord’s permitted floor loading, stated in the lease or by JTC for their estates. Get it in writing before the PE begins, because that figure sets the ceiling for every calculation downstream.

Does Singapore law require you to display the floor loading?

Yes, and almost nobody does it. Regulation 46 of the Building Control Regulations 2003 requires that in every storey of a building that is not residential, the owner exhibits at an appropriate place, “permanently and conspicuously”, a floor diagram and a notice stating the imposed load for which the floor has been designed. The notice must be incised or embossed on metal, plastic or other durable material. A printed A4 sheet in a lever arch file does not satisfy that. Neither does a line in the handover documents. Regulation 45 sits alongside it and states that no building shall be subjected to any load beyond its design loads as indicated in the approved detailed structural plans. Contravening either regulation 45 or regulation 46 carries a fine of up to $20,000, imprisonment of up to 12 months, or both. The design side is regulated too. Regulation 9(1)(e) requires detailed structural plans to clearly indicate, on the respective area of every floor plan, the imposed load for which that floor system has been designed. The number exists on the approved drawings whether or not it reaches the wall. Order the plate with the steel. It costs almost nothing at fabrication stage and becomes a small procurement project two years later when someone finally asks for it.

How do you stop the mezzanine being overloaded after handover?

Controls, not goodwill. The design load is a number that only holds if the people using the platform daily know what it is and what breaches it. Four measures do most of the work. The durable load notice and floor diagram required by regulation 46, positioned at the head of the staircase where operators see it. Marked out zones on the deck for any concentrated load such as a pallet gate landing area or a battery charger. A written rule that new equipment above a stated weight goes to the PE before it goes on the deck. And a standing item in the racking inspection round covering the platform, since ongoing rack inspections already put a trained person under the structure at intervals. The failure mode is gradual, not dramatic. A 5.0 kN/m2 picking mezzanine takes a pallet of stock at one end during a busy month, then a second, and the average across the bay stays under the limit while the local patch does not. Record what was designed and where. When the operation changes in year three, that record is the difference between a quick PE review and a full reassessment of a structure nobody has drawings for.

The number that outlives everyone

The design load is the longest lived decision on a mezzanine project. Layouts get redrawn and operators change. The kN/m2 figure in the PE’s calculations governs the platform until someone pays for a reassessment. Specify it against what you will actually stack, and put the durable notice on the wall where the law says it belongs. Send us your intended use, stacking height and the permitted floor loading for your unit, and we will tell you which design load your operation needs before you commission any drawings. Request a load assessment.

Frequently asked questions

What does 5 kN/m2 mean in actual pallets?

Roughly 500 kg spread over every square metre of deck. A 1.2m by 1.0m Euro pallet occupies 1.2m2, so a 600 kg pallet sitting alone on that footprint is already at the limit locally even though the bay average is lower. EN 1991-1-1 requires stacking height and density to be considered, not just floor area.

Can I increase the load capacity of an existing mezzanine?

Sometimes, through added secondary beams, a heavier deck or extra columns, and always through a Professional Engineer. The existing slab and base plates usually bind before the steel does. Any upgrade is building work under the Building Control Act and needs fresh BCA structural plan approval before the work starts.

Do I need a load notice on a rack supported platform?

Yes. Regulation 46 applies to every storey of a building that is not residential and makes no exception for the structural type. Rack supported platforms carry an extra reason to display it, because SS EN 15512 designs the deck and the racking as one system, so an overload above changes the members carrying the storage below.

Is a small storage loft exempt from BCA approval?

Only within a narrow limit. The First Schedule to the Building Control Regulations 2003 treats a loft as insignificant building works when it has timber flooring only and does not exceed 5 square metres. A separate item covers equipment plinths not exceeding 2,500mm in height. Anything larger is a mezzanine.

What is the difference between mezzanine floor loading and racking beam capacity?

Floor loading is the kN/m2 the deck and its frame carry across an area. Beam capacity is the kilogram rating of one pair of rack beams at one level. A 7.5 kN/m2 platform can sit above racking whose beams are rated at 3,000 kg per level, and neither figure tells you anything about the other.