Warehouse Racking Load Capacity Guide — Selective, Drive-In, Cantilever Rack Buyer's Guide

"How much weight can this rack hold?" — a question that sounds simple but has a more complex answer than the number printed in the catalogue. This guide explains how to correctly assess load capacity, choose the right rack type for your operation, and avoid the structural failures that come from buying wrong.

Four Main Rack Types

1. Selective Rack (Standard Pallet Racking)

Description: The most common racking type in Thailand. Each bay position stores one pallet, accessible directly without moving other pallets.

Spec	Typical range
Load per shelf	500–2,000 kg/shelf (per specification)
Maximum height	12m+ (depending on column profile)
Bay width	1.8–2.7m
Depth	0.8–1.2m
Pallet access	100% of all pallets (full FIFO)

Best for:

• Warehouses with many SKUs and multiple lots — each pallet must be independently accessible
• FIFO operations: food, pharmaceuticals, date-sensitive materials
• Medium-to-large warehouses requiring layout flexibility

2. Drive-In Rack (High-Density Forklift Access)

Description: Deep rack system where forklifts drive inside to place and retrieve pallets — no cross aisles. Uses approximately 80% more floor area than Selective for same pallet count.

Spec	Typical range
Load per lane/level	500–1,500 kg
Maximum height	8m
Pallet depth	4–10 pallets deep
Bay width	2.7–3.6m (per forklift size)
Pallet access	LIFO (or FIFO with drive-through 2-entry)

Best for:

• Bulk storage with few SKUs — same product in large quantities
• Cold storage rooms — minimizes wall area, reduces refrigeration cost
• Seasonal products stored and retrieved in full lot batches

⚠️ Note: Drive-In systems have higher forklift impact damage rates — column guards are essential on every upright.

3. Push-Back Rack (Automated LIFO)

Description: Pallets ride on carts on inclined rails. Loading a new pallet automatically pushes the previous one back; the front position is always the pick face.

Spec	Typical range
Load per lane	500–1,500 kg
Depth	2–5 pallets
Max height	8m
Access mode	LIFO (always pick from front)

Best for:

• Products where FIFO is not required — lubricants, construction materials, spare parts
• Higher density than Selective with easier access than Drive-In

4. Cantilever Rack (Long-Goods Storage)

Description: Arms extend from a central column on one or both sides — no horizontal beams blocking loading. Designed for goods that cannot fit in standard pallet bays.

Spec	Typical range
Load per arm	500–3,000 kg/arm
Height	3–8m+
Arm length	0.5–1.5m
Arm pitch (vertical)	Adjustable per product

Best for:

• Steel pipes, angle iron, structural profiles — 3–12m lengths
• Timber, plywood sheets, aluminum extrusions
• Windows, doors, glass panels
• Automotive long parts storage

Four-Way Comparison Table

Criterion	Selective	Drive-In	Push-Back	Cantilever
Pallet access	100% FIFO	Low — LIFO/FIFO	Medium — LIFO	100% FIFO
Storage density	Medium	Very high	High	Depends on product
SKU variety	High	Low	Low–medium	Long/large goods
Pick speed	Fast	Slow	Medium	Fast
Cold storage fit	Good	Excellent	Good	Not suitable
Cost per pallet	Low	Low (vs density)	Medium	Depends on spec
Forklift damage risk	Low	High	Low–medium	Low

Calculating Load Capacity Correctly

The number in a catalogue is a Uniform Distributed Load (UDL) — not a universal maximum for all conditions.

Information you must provide before purchasing:

1. Maximum pallet weight (kg) including pallet board
2. Pallet dimensions (W × L × H)
3. Maximum tiers per bay
4. Total height required (m)
5. Warehouse floor plan and door openings (determines minimum aisle width)
6. Floor slab load rating — old factory floors may only carry 3–5 ton/m² but a 10m-high rack may require 8–12 ton/m² at column base
7. Forklift type — turning radius determines aisle width

flowchart TD
  A["What is the pallet weight?"]
  A --> B{"> 1,500 kg/pallet?"}
  B -->|"Yes"| C["Heavy Duty
Requires custom design + foundation calculation"]
  B -->|"No"| D{"How many SKUs?"}
  D -->|"Many (>20 SKUs)"| E{"FIFO required?"}
  D -->|"Few (<5 SKUs)"| F["Drive-In or Push-Back"]
  E -->|"Yes (food/pharma)"| G["Selective Rack — full FIFO"]
  E -->|"Not required"| H["Selective or Push-Back"]
  D -->|"Long goods (>2m)"| I["Cantilever Rack"]

5 Most Common Buying Mistakes

1. Underspecifying weight — forgetting to include the pallet board weight (~15–25 kg), which causes beam deflection over time

2. Not measuring forklift clearance — a 3-way turret forklift requires 3.2m minimum aisle but if you buy standard counterbalance type you need 2.8–3.5m; rack layout must be designed for the actual forklift

3. Not checking the floor — old factory slabs may only carry 3–5 ton/m² but a 10m-high rack concentrates 8–12 ton/m² at column bases; structural survey is not optional

4. Buying unrated rack — no load certification document → insurance won't cover → no recourse if it collapses

5. No column guards — a single forklift impact on an upright can require replacing an entire bay row; column guards cost very little versus repair costs

Standards Reference

Standard	Origin	Used for
EN 15512:2020	Europe	Structural design of adjustable pallet racking
AS 4084:2023	Australia/NZ	Asia-Pacific reference for rack design
RMI ANSI MH16.1:2021	USA	Design, testing, utilization of industrial steel racks
SEMA Code	UK	Design of static racking (complementary reference)

Racking supplied by Sahawatthanakit comes with structural calculation documents per EN 15512 and AS 4084, plus load tags on every bay specifying the certified maximum load.

Services Included with Every Racking Order

• Free on-site survey (Bangkok metro area) — actual floor measurement, slab condition check, layout recommendation
• Layout design — 2D/3D plan with aisle paths and forklift flow
• Load calculation — per EN 15512 for your actual product weights
• Installation — company engineering team
• Column guards — recommended and installed simultaneously

Request a Free Layout Design

Send us your floor dimensions and pallet weight — our engineers will produce a preliminary layout before you commit.

• Phone: +66-81-866-8368 (Khun Navin) / +66-96-109-4244 (Khun Maem)
• LINE: @406rrgvm
• Email: info@sahawatthanakit1988.com
• Request a quote: Click here