80x120 Steel Warehouse Building

This page is ordered around height and clearance, because at 80x120 the 22-foot eave limits a steel warehouse sooner than the plan does.

The footprint holds 16 rack runs — 8 across by 2 deep — and leaves 21 feet of depth for a consolidation bay where slow-moving stock is reorganised without interrupting the live aisles.

Efficiency is the useful number here: 600 square feet of enclosed floor per rack run, against a 378-square-foot module. That leaves working slack around each position. The mezzanine that is added afterwards is the change order that reprices the frame.

A 80 by 120 footprint is a clearly directional plan: 9,600 sq ft enclosed by 400 ft of wall, at a 1.5:1 length-to-width proportion. Along its 120 ft dimension it takes 2 runs of rack runs at 42 ft, leaving 36 ft over — the 36 ft is where the argument about this size actually happens. Taken purely as arithmetic, 80 by 120 gives 7 rack runs across the 80 ft dimension once 15 ft is reserved for movement, and 2 deep along the 120 ft dimension. Run as a a storage-forward building where goods dwell before moving, 2 ft across is below the 12 ft this use needs to be worth planning, so there is no consolidation bay, so reorganisation happens in the live aisles and picking stops around it Travel distance is the operating cost that grows fastest as a floor gets larger.

This footprint is planned as a storage-forward building where goods dwell before moving. Spent as a square 98 by 98 instead, the same 9,600 sq ft would stand 9 rack runs across rather than 7, and would trade this plan's length for parallel access. That is the width-against-depth decision this footprint has already made. Compared with a 80 by 90 of the same width, the extra depth here adds run rather than reach: it buys about 2 rack runs in line, and every position past the second is retrieved by moving what stands in front of it. A building of this size behaves like a small yard under a roof: zones need to be defined, signed and left alone, or they migrate. Movement is infrequent per item but constant in aggregate, so the aisles are lightly but continuously used. That pattern tolerates narrow aisles better than a high-throughput floor would. Floor flatness for handling equipment is set at the pour and is difficult to correct afterwards.

The stored configuration carries a 22-foot eave and computes to 35.3 feet at the ridge on a 4:12 pitch — a 13.3-foot rise across 80 feet. Height is therefore not uniform, and the sidewall is the constraint. Two feet of spare width reads as nothing on a plan and as a great deal when a machine is being turned.

Storage height is the useful dimension here and is the one thing a dwell-heavy building genuinely converts into capacity, subject to the racking supplier's confirmation for the specific system.

The handling pattern this floor could equally be run as is a cross-dock floor where goods are sorted rather than stored: there is no marshalling depth, so goods are broken down in the lanes and the second face waits for the first. Long rack runs take the depth and a working strip takes the front. Placing the working strip at the far end is the arrangement that makes every trip a round trip.

The 21-foot leftover depth is 1,680 square feet across the full width — deep enough to plan deliberately, and at this footprint it goes to a consolidation bay where slow-moving stock is reorganised without interrupting the live aisles. Storage expands until it meets a wall, so give it a wall on purpose.

Spare width is the more valuable of the two leftovers here: a continuous 8-foot strip beats the same area stranded at the end of the run, because it touches every position along the way. Judge the plan by what has to happen on the worst day of the year, not on an average one.

Spent as a square 98 by 98 instead, the same 9,600 sq ft would stand 9 rack runs across rather than 7, and would trade this plan's length for parallel access. That is the width-against-depth decision this footprint has already made. Compared with a 80 by 90 of the same width, the extra depth here adds run rather than reach: it buys about 2 rack runs in line, and every position past the second is retrieved by moving what stands in front of it. A building of this size behaves like a small yard under a roof: zones need to be defined, signed and left alone, or they migrate. Movement is infrequent per item but constant in aggregate, so the aisles are lightly but continuously used. That pattern tolerates narrow aisles better than a high-throughput floor would. Floor flatness for handling equipment is set at the pour and is difficult to correct afterwards. That movement pattern, not the 9,600-square-foot total, is what decides whether the leftover 21 feet is useful here.

The 80-foot gable can carry 8 openings, one per rack run, with 8 feet of wall left for piers between and beside them — the arrangement that keeps each position independently reachable. The plan is only as good as the route into it, which is a site question rather than a building one.

The 80 ft ends and the 120 ft sides offer very different opening budgets: 80 ft of end wall has room for one wide opening or two modest ones, while 120 ft of side wall can carry several without the openings competing. On this plan the deciding factor is whether rack run layout or slow-moving stock planning should be the first thing reached from the door.

Handling equipment works between vehicle and racking, so staging depth in front of the doors is functional space, not spare space.

Nominal bay division computes to 5 bays at about 24 feet, wider than the 9-foot module — so a position can sit inside a bay without a frame line splitting it. Rows that cannot be entered independently end up used as one long space.

With 2 rows deep, the rear row is behind the front one. Without a route past it, those rack runs become storage positions rather than working ones — the real cost of depth at this width. Circulation width is the first thing surrendered under pressure and the first thing missed afterwards.

This floor extends by adding runs at the same orientation. Reorienting racking in an extension creates two operations in one building.

Configured as a storage-forward building where goods dwell before moving, 80x120 is judged on whether the 16 rack runs it holds match the operation, and on whether the 8 feet of spare width leaves the route this mode depends on.

• Does the work need racking or work zones on both sides with a full vehicle lane down the middle, or does it need a second lane that this 80-foot span cannot give?
• Is the 120-foot length being bought for depth, or for the repeated bays — a long repeating bay sequence, so segment boundaries are set by bay lines rather than by walls?
• What racking height is planned, and is the clear height measured under the frame?
• Does the aisle module match the handling equipment you use?

• 50x80 moves the count from 16 to 2 rack runs (2 across by 1 deep), which is the reason to choose between them.
• 40x100 moves the count from 16 to 2 rack runs (2 across by 1 deep), which is the reason to choose between them.
• 60x80 moves the count from 16 to 4 rack runs (4 across by 1 deep), which is the reason to choose between them.

Because this footprint is planned as a storage-forward building where goods dwell before moving, the useful next reads are different from the ones a differently shaped steel warehouse suggests: rack run layout, slow-moving stock planning, consolidation bay planning.

No price appears on this page. The quantities that scale an estimate at 80x120 are 9,600 square feet of slab, 177.8 cubic yards of nominal concrete, 8,800 square feet of wall cladding and 10,119 square feet of roof cladding. Whoever operates the building daily should read the plan before it is frozen, because they know where the pinch points are.

Proportion drives cost here as much as size does: 400 ft of wall around 9,600 sq ft is 0.042 ft of wall per enclosed square foot, and a squarer plan of the same area would carry less. What moves the figure further on a a storage-forward building where goods dwell before moving is the fit-out rack run layout implies, along with framed openings and the height chosen for the 80 ft span.

• clear height for racking positions
• the loading openings and their equipment
• floor requirements under racking and handling equipment, which are engineering items
• yard area for vehicle turning