How this is calculated
Inspect the versioned inputs.
| Constant | Value | Scope & source |
|---|---|---|
| benchHeadroomMin | 1.1 m | Manufacturer ergonomic guidance. harvia-benches ↗ Verified 2026-11-08 |
| benchHeadroomMax | 1.2 m | Manufacturer ergonomic guidance. harvia-benches ↗ Verified 2026-11-08 |
| benchStep | 0.35 m | Manufacturer ergonomic suggestion; adapt for access needs. harvia-benches ↗ Verified 2026-11-08 |
Input defaults that are not sourced measurements are illustrative planning assumptions. Exact unit definitions, the 52-week convention and algorithm details are in the shared methodology.
Worked example
An example you can inspect.
For a 2.2 m ceiling, the upper bench guidance spans 1.0–1.1 m above the floor. A 0.35 m step below the lower end gives 0.65 m.
Work from a common finished-floor datum.
Enter ceiling height and heater-top height from the same finished floor. Mixing a structural ceiling measurement with a finished floor measurement shifts the whole section. A raised platform or a heater mounted above its minimum position can also change the relationship. Record those details before comparing the drawing with a product installation sheet. The planner assumes a horizontal ceiling and a simple two-level section. It does not solve a sloped ceiling, accessibility transfer, ladder, guardrail or structural support detail. Those need a separate measured design.
Read the range as headroom geometry.
The upper-bench range comes from subtracting the cited ceiling-to-bench headroom interval from your ceiling height. The lower bench is an illustration using the cited step interval. These numbers describe a geometric relationship. They do not predict the air temperature at a person's head, torso or feet, and they do not establish a comfortable experience for every body size. If the section does not fit, the tool withholds a usable arrangement instead of shrinking the source guidance invisibly. Reconsider the room height, bench configuration and equipment with the designer.
Compare heater height without inventing a temperature gradient.
The entered heater top is drawn beside the benches so you can discuss their relative elevations. The result states whether the lower bench is above or below that entered height. It applies no degrees-per-centimetre rule and no numerical comfort penalty. Actual thermal conditions depend on the installation and operation, including ventilation and the heater design. A visual relationship alone cannot validate those conditions. Confirm the exact product's mounting and overhead clearances separately; the height comparison must never be used to reduce a required clearance.
Check access and seated posture in the real space.
Mark the proposed elevations on a wall or a full-size mock-up. Consider how the intended users will step up, sit, stand and leave, including where their feet and hands need support. The tool's section does not reserve a clear aisle or design a safe step. Compare the proposed seat with the intended backrest and any adjacent wall fixtures. Record the final dimensions and unresolved questions in your project notes, then review them alongside the room plan. A passing calculation is only one input to that discussion, not a construction instruction.
Record the chosen configuration.
If you select a different point within the displayed upper-bench range, record that elevation explicitly. The lower-bench illustration does not redesign itself around every possible construction detail. Compare the final section with the floor plan, the door and the access route as one design. Export or print the assumptions you actually discussed, and replace that note when the ceiling, heater mounting or bench arrangement changes.
Questions, considered
Questions about this tool
How should I interpret the bench & ceiling height planner result?
Ergonomic guidance is not an accessible-design, structural or fire-code check. Feet relative to heater top are context, not proof of temperature distribution. Explore bench elevations against the ceiling and heater top, using manufacturer ergonomic guidance with clear, explicitly stated geometric limits.
Which assumptions matter in the bench & ceiling height planner?
Upper bench elevation = ceiling height − 1.1 to 1.2 m headroom. Illustrative lower bench = lower upper-bench elevation − 0.35 m. Compare the entered heater top geometrically. The color gradient illustrates warmer upper air; no degrees-per-height prediction is made.
Primary sources
Follow the source.
- Harvia — What to consider when choosing sauna benches ↗
Questions on bench depth, width, roof separation, opposing benches and step height
Manufacturer ergonomic planning guidance, not an occupancy, accessibility or structural code.
Checked 2026-11-08 - HUUM CORE US installation and operation manual, v9 ↗
Printed pp.4–6: sizing, Tables1–3 and installation; pp.9–11: room and ventilation
CORE9/11 rows are consistent with P/V. CORE6 is excluded: its 240V table pairs6.5kW with25A, which does not match P/V; the208V row also conflicts. Preserve this discrepancy rather than silently correct a manufacturer's table.
Checked 2026-11-08