How much clear height will you really get?
Enter your floor height and what hangs under the slab. See the clear height you actually get, drawn to scale, and the biggest duct that still fits.
All values in millimetres. Typical figures are starting points, not design values. Check minimum clear heights with your local building bylaws and the National Building Code, and confirm services depths with your engineers. This tool does not replace a coordinated model.
Questions
What is a ceiling void?
The ceiling void is the space between the underside of the slab or beam and the finished ceiling, where ducts, cable trays, pipes and sprinkler lines run.
Should services run below or inside the beams?
Running services through beam openings can save a lot of height but needs early coordination with the structural engineer. Running them below beams is simpler but costs the full beam depth plus the services.
Are the default values design values?
No. They are typical starting points. Use your own project values and confirm them with the structural and services engineers.
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