What's the difference between roof height and clear height?

Roof height is the building's overall height; clear height is the unobstructed space below the lowest obstruction, sprinklers, lighting or bracing, which is what actually limits how tall racking can go. Always ask for clear height specifically.

Can floor loading capacity be upgraded after the building is leased?

Sometimes, with additional slab work, but it's expensive and disruptive compared with checking the existing rating before signing. It's not something to assume can be fixed cheaply later.

Why does slab flatness matter more for some racking than others?

Narrow-aisle systems run trucks with very tight clearances against the racking, so floor variation that a standard counterbalance forklift shrugs off can be a real problem for narrow-aisle configurations.

Should I check power capacity even if I'm not running automation?

Yes. Electric forklift charging, lighting and basic building services all draw on the same connection, and undersizing it is a common oversight even in straightforward ambient warehouses.

What to Check in a Shed Before You Sign

Before you commit to a warehouse, the building itself needs checking against what you actually plan to store and how you plan to move it, not just how many square metres the lease quotes. Six things decide whether a shed will do the job: clear height, floor loading, slab flatness, column grid, dock configuration and power.

Last updated 2026-08-24

Clear height

Clear height is the unobstructed vertical space from the floor to the lowest overhead obstruction, sprinkler heads, lighting, roof bracing, not the roof height quoted in a marketing brochure. It's the single biggest driver of how much pallet storage capacity a building can actually hold, because racking height is what multiplies floor area into cubic storage.

Two buildings with identical floor area can hold very different amounts of stock depending on clear height alone, which is why how beam levels actually get set within that height is worth understanding before assuming a taller-sounding building automatically means more capacity.

Floor loading and slab flatness

The slab has to be rated for the point loads your racking anchors will apply, not just able to take a forklift driving across it. An older slab built for lighter use can be structurally unsuited to a dense modern racking system even though it looks like ordinary warehouse concrete.

Flatness matters separately from loading capacity. A slab with too much variation across its surface causes problems for narrow-aisle equipment specifically, where tight tolerances between the truck and the racking leave little room for a floor that isn't level. What actually makes a slab suitable is worth checking directly rather than assuming a warehouse floor is a warehouse floor.

Column grid and dock configuration

The column grid, the spacing between structural columns holding the roof up, decides how racking rows can actually be laid out, because a column landing in the wrong place can force an awkward bay width or waste an entire aisle's worth of space working around it. A wide, regular grid gives far more flexibility in how aisles and rows get planned than a tight or irregular one.

Dock configuration, how many dock doors, their height and whether they're level access or dock-levellers, decides how fast trucks can actually load and unload, which matters as much for day-to-day operating cost as anything about the racking inside. Dock and staging area design that doesn't match your actual truck volume becomes a bottleneck no amount of internal racking efficiency fixes.

Power

A warehouse running electric forklifts, conveyor systems, or refrigeration needs power capacity to match, and it's a specification item that's easy to overlook until equipment doesn't run properly. Checking available capacity, and whether upgrading it is even possible on the existing connection, rather than assuming it can be added later, avoids a costly surprise after fit-out has already started. This matters even more for a site running lithium forklift batteries, which draw differently for charging than older lead-acid fleets.

Why this is where property becomes a racking decision

Everything above eventually turns into a racking layout decision. Clear height sets how many beam levels are possible, the slab decides what racking can actually be anchored where, and the column grid decides bay widths before a single frame gets ordered. Getting the building specification right first is what makes the actual racking installation straightforward rather than a series of compromises worked around a building that wasn't checked properly beforehand.

It's worth walking the empty shed with these six things on a list before signing anything, rather than relying on a floor plan and a listing photo. A building that looks right on paper can still fail on clear height or slab rating in ways that only show up once you're trying to fit racking into it.

Common questions

What's the difference between roof height and clear height?: Roof height is the building's overall height; clear height is the unobstructed space below the lowest obstruction, sprinklers, lighting or bracing, which is what actually limits how tall racking can go. Always ask for clear height specifically.
Can floor loading capacity be upgraded after the building is leased?: Sometimes, with additional slab work, but it's expensive and disruptive compared with checking the existing rating before signing. It's not something to assume can be fixed cheaply later.
Why does slab flatness matter more for some racking than others?: Narrow-aisle systems run trucks with very tight clearances against the racking, so floor variation that a standard counterbalance forklift shrugs off can be a real problem for narrow-aisle configurations.
Should I check power capacity even if I'm not running automation?: Yes. Electric forklift charging, lighting and basic building services all draw on the same connection, and undersizing it is a common oversight even in straightforward ambient warehouses.

Part of our guide to leasing industrial space.