# Warehousing and Logistics Buildings: What They Demand

> Warehouse construction delivers a storage and distribution building whose value is set by what it lets the operator do: rack height, truck speed, dock throughput and stock protection. Floor, clear height, docks, roof, lighting and fire strategy all follow from the racking and handling plan, so that plan has to be fixed before the slab and frame are designed.

## A warehouse is sold on cubic capacity and throughput

A warehouse earns its rent, or justifies its capital, by how many pallet positions
it holds and how fast goods move in and out. Floor area is only the start of that.
Two sheds of the same footprint can differ widely in usable capacity once clear
height, floor quality, dock arrangement and fire protection are taken into account.

The common misconception is that a warehouse is a simple box and the hard part is
the price of steel. In practice the expensive mistakes are quieter: a slab that
cannot take the racking an operator wants, a haunch or sprinkler main that costs a
pallet level, docks that queue trucks at peak hour, or a roof that leaks over stock.
Each one is either rework in a building already in use or a permanent loss of
capacity.

## Where Hagerstone services apply

| Building element | What it has to do | Service |
| --- | --- | --- |
| Storage shed and frame | Large column-free spans, clear height set by the racking | [PEB industrial buildings and warehouses](/services/peb/peb-industrial-buildings-and-warehouses) |
| Roof and wall envelope | Watertight laps and rooflights, insulation where stock needs it | [PEB roofing and wall cladding](/services/peb/peb-roofing-and-wall-cladding) |
| Warehouse floor | Flatness, loading and joints matched to racking and trucks | [Industrial flooring and hardstanding](/services/construction/industrial-flooring-and-hardstanding) |
| Yard, docks and approaches | Truck turning, dock aprons, surface drainage | [Site development and external works](/services/construction/site-development-and-external-works) |
| Pick floors and platforms | Steel mezzanines tied into the frame | [Mezzanine floors and steel structures](/services/peb/mezzanine-floors-and-steel-structures) |
| Fire protection | Hydrant, sprinkler and pump room to the consultant's design | [Firefighting systems](/services/mep/firefighting-systems) |
| Power and lighting | Incoming supply, high-bay lighting, dock equipment | [Electrical works HT/LT](/services/mep/electrical-works-ht-lt) |

## The racking plan sets the floor and the height

Everything in a warehouse is measured from the racking. The rack type and the
handling equipment decide how high goods are stacked, how narrow the aisles are and
how flat the floor must be. Narrow-aisle trucks lifting to height are far less
tolerant of an uneven floor than counterbalance forklifts in wide aisles, which is
why floor flatness is specified for the truck and measured to a defined method such
as **ASTM E1155**. Racking tolerances and clearances are covered separately under
**EN 15620**, which explicitly leaves the floor to its own specification.

Clear height is lost from the top down. The portal frame haunch, sprinkler mains,
light fittings and any ductwork all sit below the roof sheet, so the useful number
is the height to the lowest obstruction across the racking zone. That is a
coordination task between the steel, fire and electrical designs, settled before
fabrication. The detail of floor loads, joints and curing is covered in
[decide the racking before the warehouse slab](/blog/warehouse-floor-decide-the-racking-before-the-slab).

## Docks, roof and lighting decide daily throughput

**Docks** fix more of the site plan than most owners expect: door count and type,
leveller pits, canopies, apron levels, yard depth and the turning space trucks need.
Inbound and outbound patterns change the answer, which is why
[warehouse loading dock design](/blog/warehouse-loading-dock-design) starts from the
operator's volumes rather than a standard count.

**Roofs** on large sheds fail at the same few places: rooflights, end laps,
fasteners and gutters. A leak over a racked aisle damages stock and stops picking,
so laps, fixings and rooflight upstands deserve inspection as they go in. See
[warehouse roof leaks at skylights and sheet laps](/blog/warehouse-roof-leaks-skylights-and-sheet-laps).

**Lighting** has to reach the faces of the racks, not just the aisle floor, and
fittings must avoid the trucks' lift path. Daylight from rooflights helps, but only
if it is planned with the roof layout. The general framework for working interiors
is in **IS 3646 (Part 1)**; the practical choices are covered in
[warehouse lighting with high-bay fittings and daylight](/blog/warehouse-lighting-high-bay-and-daylight).

## Fire protection is a framework set early

Storage buildings fall under the fire and life safety provisions of **NBC 2016,
Part 4**. What is stored, how it is packed, how high it is stacked and how the
racking is arranged all influence the protection the fire consultant designs, and
some arrangements bring sprinklers into the racking itself, which changes the rack
design. Compartmentation, fire tender access around the building and the pump room
location also shape the site plan. These are decided by the fire consultant and the
authority having jurisdiction, and the earlier they see the racking plan the less
the building has to change.

## Common mistakes

- **Designing the shed before the racking.** The frame, slab and sprinklers get
  fixed around an assumption nobody wrote down.
- **Quoting height to the eaves.** The operator loses a pallet level to the haunch
  or the sprinkler main.
- **One floor specification for everything.** Dock zones, racking zones and staging
  areas see different loads and traffic.
- **Treating docks as doors.** Apron levels, leveller pits and yard depth are civil
  works that cannot be added cheaply later.
- **Leaving rooflights to the sheeting crew.** Upstands and laps around them are
  where large roofs most often leak.

## What to ask your warehouse builder

- Which racking system and handling equipment is the design based on, in writing?
- What is the clear height to the lowest obstruction across the racking zone?
- How is floor flatness specified, and how will it be measured at handover?
- How were the dock count, type and yard depth worked out?
- Has the fire consultant seen the stored goods and racking plan?
- What structural allowance has been made for mezzanines, plant or future solar?

## Standards referenced

Fire and life safety for storage occupancy under **NBC 2016, Part 4**; steel design
to **IS 800:2007**; racking tolerances and clearances in **EN 15620**; floor flatness
measurement to **ASTM E1155**; interior lighting in **IS 3646 (Part 1)**. Loads,
floor specification, fire protection and lighting levels for a particular warehouse
are established by the project's structural, fire and electrical consultants and the
authority having jurisdiction.

## Frequently asked questions

### What should be decided before a warehouse is designed?

The racking system, the handling equipment and the storage height. Together they set the clear height, the floor flatness and loading, the column grid and much of the fire protection approach. If the operator or tenant is not yet known, the design should state the racking assumption it is built around, so a future occupier can see what the building supports.

### Is a PEB frame the right structure for a warehouse?

It is the usual choice for single-storey storage buildings, because pre-engineered steel gives large column-free spans and fabrication can run in parallel with foundations. The frame still has to be designed for the actual loads, including any mezzanines, roof-mounted plant or future solar, by the project's structural engineer to IS 800:2007 and the applicable loading codes.

### What does clear height actually mean in a warehouse?

It is the usable height below the lowest obstruction, which is usually the haunch of the portal frame, sprinkler pipework, lighting or ductwork rather than the roof sheet. The figure that matters to an operator is the height available for the top pallet plus its handling clearance, so ask for clear height measured to the lowest obstruction across the racking zone.

### How many loading docks does a warehouse need?

It depends on the throughput, the truck types, how long each vehicle stays at the dock and whether inbound and outbound share doors. The operator's peak-hour volumes are the starting point. Dock positions also fix yard depth, truck turning space and apron levels, so the number and type should be settled before the site plan is frozen.

### Who decides the fire protection for a warehouse?

The fire consultant designs it and the authority having jurisdiction approves it, working under NBC 2016 Part 4. What is stored, how high it is stacked and how the racking is arranged all affect the approach, so the stored goods and racking plan need to be described to the consultant early rather than after the building is complete.

## Sources

- [NBC 2016, Part 4](https://www.bis.gov.in/standards/national-building-code/) — Fire and life safety - storage occupancy
- [IS 800:2007](https://standards.bis.gov.in/website/published-standards/department-wise) — General construction in steel - code of practice
- [EN 15620](https://standards.cencenelec.eu/ords/f?p=CEN:105) — Steel static storage systems - adjustable pallet racking - tolerances, deformations and clearances
- [ASTM E1155](https://www.astm.org/products-services/standards-and-publications.html) — Standard test method for determining FF floor flatness and FL floor levelness numbers
- [IS 3646 (Part 1)](https://standards.bis.gov.in/website/published-standards/department-wise) — Code of practice for interior illumination - working interiors

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Source: https://hagerstone.com/industries/warehousing-and-logistics