How do you calculate shop bay utilization?

Divide occupied bays by total available bays. With 8 bays occupied out of 250 available, utilization is 3.2%, which is 91.8 points below a 95% target.

What is a good shop bay utilization rate?

For a vessel shop, sustained occupancy of 80-90% is healthy; above 95% usually means bays are congested and jobs wait on cranes. The 3.2% in the example is extremely low and points to either a data-entry issue or a badly under-loaded shop.

Why is my utilization so low in the example?

8 out of 250 is only 3.2%, which almost certainly means the 'total available' figure counts something other than physical bays, such as total scheduled hours or slots. Make sure both inputs use the same unit of bays.

Occupancy vs productive utilization: what is the difference?

This tool measures whether a bay is occupied, not whether it is producing. A bay tied up by a vessel waiting on RT sign-off counts as occupied but adds no throughput, so pair the rate with a stall count.

How do I close the gap to my target?

The example gap is 91.8 points. Realistically you close a utilization gap by pulling more work onto the floor, clearing bays stalled on inspection, and staggering start dates so vessels flow through hydro and paint rather than piling up.

Should stalled bays count as occupied?

Physically yes, but for decision-making track them separately. A high occupancy driven by stalled vessels is worse than moderate occupancy with everything moving, since stalls hide real available capacity.

Tank, Vessel & Pressure Equipment Fabrication calculator

Shop Bay Utilization Calculator

Shop Bay Utilization measures what fraction of a fabrication shop's assembly bays are actively occupied by vessels in progress, and how far that sits from your target. Plant managers and schedulers in tank and pressure-vessel shops use it to spot idle floor capacity, justify taking on more work, or flag when bays are clogged with vessels stalled waiting on hydro, RT sign-off, or paint. It matters because a heated, crane-served fabrication bay is one of the most expensive resources on the floor, and low occupancy quietly burns overhead. Tracking it turns a vague sense of 'the shop feels empty' into a number you can act on.

What this calculator does

Shop Bay Utilization measures what fraction of a fabrication shop's assembly bays are actively occupied by vessels in progress, and how far that sits from your target.
Use it when shop bay utilization in tank, vessel and pressure equipment fabrication needs a clean rate and gap-to-target you can put on a tier board.
It computes the ratio of occupied bays to total available bays as a percentage, and the point gap to your target occupancy.

Formula used

Shop Bay Utilization rate = affected amount ÷ total amount
Gap to target = target rate - calculated rate

Inputs explained

Fabrication bays currently occupied:
Total fabrication bays available:
Target bay occupancy rate:

How to use the result

Use it in weekly capacity reviews or when deciding whether to bid additional work against available floor space.
A raw occupancy count treats every bay as equal and does not weight for bay size, crane capacity, or whether an occupied bay is actually producing versus stalled.

Current U.S. benchmarks

U.S. iron and steel imports ran $2.1B in May 2026 (Census International Trade). The U.S. ran a trade deficit of $0.4B in the category that month. Import volumes are the pressure gauge behind tariff and reshoring decisions.
Steel mill PPI stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. New factory orders are up 2.3% year over year (Census).
The U.S. has 53,790 fabricated metal products establishments employing about 1,441,471 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate shop bay utilization? Divide occupied bays by total available bays. With 8 bays occupied out of 250 available, utilization is 3.2%, which is 91.8 points below a 95% target.
What is a good shop bay utilization rate? For a vessel shop, sustained occupancy of 80-90% is healthy; above 95% usually means bays are congested and jobs wait on cranes. The 3.2% in the example is extremely low and points to either a data-entry issue or a badly under-loaded shop.
Why is my utilization so low in the example? 8 out of 250 is only 3.2%, which almost certainly means the 'total available' figure counts something other than physical bays, such as total scheduled hours or slots. Make sure both inputs use the same unit of bays.
Occupancy vs productive utilization: what is the difference? This tool measures whether a bay is occupied, not whether it is producing. A bay tied up by a vessel waiting on RT sign-off counts as occupied but adds no throughput, so pair the rate with a stall count.
How do I close the gap to my target? The example gap is 91.8 points. Realistically you close a utilization gap by pulling more work onto the floor, clearing bays stalled on inspection, and staggering start dates so vessels flow through hydro and paint rather than piling up.

Last reviewed 2026-05-12.