Why use contribution instead of sales revenue?

Variable costs avoided during downtime reduce the economic loss. Contribution deducts those avoided costs from missed sales.

What if production is fully recovered later?

Enter zero unrecovered share. Only the entered additional restart expense remains.

Should idle payroll be added automatically?

No. Add only incremental expenses not already represented in the contribution or restart estimate, avoiding double counting.

Why is exposure per hour blank at zero downtime?

Dividing by zero lost hours has no meaning. The total can still show a separately incurred restart expense.

Heat Treatment, Furnaces & Thermal Processing calculator

Furnace Downtime Cost Calculator

Estimate the economic exposure remaining after any planned production recovery. Enter downtime, contribution per productive hour, unrecovered share and additional restart cost.

What this calculator does

Estimate unrecovered production contribution and incremental restart expense from a furnace downtime event.

Formula used

Unrecovered production time = downtime × unrecovered output share ÷ 100
Contribution loss = unrecovered production time × contribution per productive hour
Total downtime exposure = contribution loss + additional restart cost
Exposure per lost hour = total downtime exposure ÷ positive downtime

Inputs explained

Furnace Downtime: Recorded furnace hours lost during the event.
Contribution per Productive Hour: Lost sales less avoided variable costs per productive hour.
Output Not Recovered Later: Share of the missed contribution not recovered by later production.
Additional Restart Cost: Incremental restart expense outside the contribution estimate.

How to use the result

Best suited to downtime economic review, repair priority comparison.
This estimate does not measure total lost revenue or accounting profit. Excludes penalties, damaged inventory and recovery overtime unless included separately in restart expense.

Current U.S. benchmarks

Industrial electricity averages 9.77 cents per kWh across the U.S. (EIA, Jul 2026), up 4.7% from a year earlier. Energy-intensive steps carry this directly into unit cost.

Common questions

Why use contribution instead of sales revenue? Variable costs avoided during downtime reduce the economic loss. Contribution deducts those avoided costs from missed sales.
What if production is fully recovered later? Enter zero unrecovered share. Only the entered additional restart expense remains.
Should idle payroll be added automatically? No. Add only incremental expenses not already represented in the contribution or restart estimate, avoiding double counting.
Why is exposure per hour blank at zero downtime? Dividing by zero lost hours has no meaning. The total can still show a separately incurred restart expense.

Last reviewed 2026-10-06.