HVAC and household energy

Kitchen Exhaust Calculator

Compare room-volume exhaust airflow with an appliance-based kitchen ventilation minimum.

CalculationKitchen ventilation estimate
Comparisonexhaust units cases
PrivacyLocal exhaust units
Kitchen ventilation estimate

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The values shown are a worked example, not a recommendation or live price.

Planning note: Kitchen Exhaust Calculator simplifies climate, envelope, infiltration, occupancy, and equipment data. Confirm the final exhaust units selection with a recognized load method and qualified professional.

Measure the exhaust units line in the direction described by Kitchen length (ft) and keep that direction consistent.

Use the actual Kitchen width (ft) that controls this exhaust units calculation, not a product name or rough assumption.

Measure Ceiling height (ft) for exhaust units at the condition being modeled; use a separate run when this dimension changes.

Use the value that controls this exhaust units case and rerun the page when it changes.

Enter the usable Appliance-based minimum (CFM) from the data sheet, quote, field test, or production record.

Calculations stay in this browser and are not transmitted.

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Your estimate will appear here

Change the example inputs to match the project.

How the answer should be checked

If the exhaust units number drives a decision, save the alternate case that shows what happens when the main assumption changes.

Check whether Kitchen length (ft) and Kitchen width (ft) describe the same physical condition before trusting the exhaust units result.

Values to replace before calculating

The sample values show how exhaust units is calculated. Replace them with the exhaust units dimensions, rates, factors, and allowances from the job.

Kitchen length (ft)
Measure the exhaust units line in the direction described by Kitchen length (ft) and keep that direction consistent.
Kitchen width (ft)
Use the actual Kitchen width (ft) that controls this exhaust units calculation, not a product name or rough assumption.
Ceiling height (ft)
Measure Ceiling height (ft) for exhaust units at the condition being modeled; use a separate run when this dimension changes.
Target air changes per hour
Use the value that controls this exhaust units case and rerun the page when it changes.
Appliance-based minimum (CFM)
Enter the usable Appliance-based minimum (CFM) from the data sheet, quote, field test, or production record.

Resolve drawing and field conflicts around Kitchen length (ft) for exhaust units before calculating; averaging them can make the estimate less useful.

Treat Kitchen width (ft) as a source-controlled value on the exhaust units worksheet. If it comes from a catalog, quote, test, or field note, record that source beside the saved exhaust units result so later changes are traceable.

If exhaust units is one part of a larger scope, Bathroom Fan CFM Calculator can estimate exhaust airflow from bathroom volume and selected air changes.

Checks outside the model

Use the displayed exhaust units inputs as the model boundary; climate, infiltration, thermal bridges, solar gain, occupancy, equipment curves, and controls still need project review before purchase or construction.

Kitchen Exhaust Calculator simplifies climate, envelope, infiltration, occupancy, and equipment data. Confirm the final exhaust units selection with a recognized load method and qualified professional.

exhaust units: What is included in this estimate

Compare room-volume exhaust airflow with an appliance-based kitchen ventilation minimum.

Treat the exhaust units number as one modeled case and compare it with a second realistic case before relying on it.

A exhaust units result is strongest when every entered value belongs to the same drawing revision or field measurement.

The page works best when exhaust units is treated as one defined scope line. If the project contains unlike areas, save separate results before combining totals on the exhaust units worksheet.

Calculation path for exhaust units

From Kitchen length (ft) to Appliance-based minimum (CFM): Required CFM is the greater of the room-volume airflow and the appliance-based minimum. Recalculate when Kitchen length (ft) or Appliance-based minimum (CFM) changes.

Keep schedule, efficiency, climate, and rate assumptions visible when comparing exhaust units scenarios.

During early planning, mark the weakest exhaust units assumption and revisit it when better information is available.

Before you use the result

  • Save the utility rate, weather assumption, and operating schedule with the result while checking Kitchen length (ft).
  • Keep comfort, humidity, and ventilation requirements outside the simple energy arithmetic on the exhaust units worksheet.

exhaust units: Input questions

Which input should be sensitivity-tested for exhaust units when the result looks low?

Start with Kitchen length (ft), then vary Appliance-based minimum (CFM). Energy results can swing when operating schedules, efficiency assumptions, or weather assumptions move together for exhaust units. Use the answer as a exhaust units planning note, then verify Kitchen length (ft) before final use.

Why might a utility bill disagree with the result for exhaust units for exhaust units planning?

Bills combine weather, schedules, standby loads, rate tiers, taxes, and equipment cycling that a single calculator cannot fully reproduce on the exhaust units worksheet.

Can the default energy price be treated as current for exhaust units before comparing scenarios?

No. Replace it with the marginal rate from the applicable tariff or recent bill before using a cost result on the exhaust units worksheet.

Should one average month be annualized for exhaust units when Kitchen width (ft) is uncertain?

Only when the month represents the season being modeled with Kitchen length (ft) as the audit point. Heating, cooling, ventilation, and standby loads rarely stay flat across the year before carrying exhaust units forward.

What should be saved with the result for exhaust units when a supplier value changes?

Save the source of the load, the assumed schedule, the efficiency basis, and the rate date for this exhaust units scope. Those notes make later comparisons easier to explain with Kitchen length (ft) as the audit point. If Kitchen length (ft) came from the field, keep the measurement date with the result.

What the default inputs show for exhaust units

Default sample inputs: Kitchen length (ft) = 16, Kitchen width (ft) = 12, and Ceiling height (ft) = 9.

Estimated result: 432 CFM.

When exhaust units changes unexpectedly, check Kitchen length (ft) first and then the conversion or allowance field.

The next dependent exhaust units calculation may be Air-Change Rate Calculator, especially when you need to calculate actual air changes per hour from room volume and measured or rated CFM.

Jobsite context for exhaust units

The Kitchen Exhaust Calculator uses dedicated kitchenExhaust inputs rather than a generic package or area substitute. Check each displayed exhaust units assumption against product data, field conditions, and the decision described in the result.

Use Kitchen length (ft) as the first exhaust units audit point when the result looks unexpectedly high or low.

Look for the condition that makes exhaust units non-repeating: a different room, slope, product size, zone, rate, or access constraint. That condition usually deserves its own run instead of being averaged into Kitchen length (ft).