How do I use the duct heater calculator?

Enter your design inputs below and click Calculate. The tool applies UK building services methods for duct heater and reports results with assumptions.

What standard applies to duct heater?

Confirm the relevant British Standard or Approved Document on your project. This calculator is for first-pass sizing — verify against the issued specification before sign-off.

Can I save duct heater results in BuildFlo?

Sign up for a free BuildFlo account to save calculation results in your project workspace and attach them to your calculation folder.

BuildFlo Design Guide · Ventilation · Ventilation

duct heater calculator for UK building services

Supply air / duct heater kW from airflow and entering → leaving air temperatures (Q = V̇·ρ·cp·ΔT). Free UK duct heater calculator with ventilation guidance.

What this calculator does

Duct heater helps UK building services engineers with supply air / duct heater kw from airflow and entering → leaving air temperatures (q = v̇·ρ·cp·δt). The calculation follows Ventilation methods used in everyday MEP design — enter your project inputs below for a first-pass result.

Whether you searched for "duct heater", "duct heater calculator", or "how to duct heater", this page gives you a working tool plus the context to use it on a real job.

When to use it

Use this for early-stage sizing and sanity checks on UK building services work. It is not a substitute for issued calculations — verify against the project specification, drawings, and relevant standard before sign-off.

How to use it

1. Fill in the inputs for your scenario (defaults are starting points only). 2. Click Calculate — results include the method and assumptions where applicable. 3. Verify against the project specification and relevant standard before issuing.

Typical output unit: kW.

Tips

Defaults are indicative — replace with project-specific values from the architect, structural, or MEP spec.
For issued calculations, save results in your BuildFlo project and attach to the calculation folder.
Need the regulation citation? Open BuildFlo chat in the app and ask about duct heater under UK standards.

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Frequently asked questions

How do I use the duct heater calculator?: Enter your design inputs below and click Calculate. The tool applies UK building services methods for duct heater and reports results with assumptions.
What standard applies to duct heater?: Confirm the relevant British Standard or Approved Document on your project. This calculator is for first-pass sizing — verify against the issued specification before sign-off.
Can I save duct heater results in BuildFlo?: Sign up for a free BuildFlo account to save calculation results in your project workspace and attach them to your calculation folder.