What the planner produces
SteamDesignPro turns room inputs into a visual planning record: enclosure dimensions, calculated volume, a preliminary generator selection, electrical characteristics published for that model, a compatible control and steam-head path, placement warnings, and a discussion checklist. Kohler's own calculator also begins with room length, width, and height, then asks about the shower system and steam-head shape. Kohler steam calculator (official Kohler source)
The output is deliberately a coordination artifact, not a permit set. It should help an owner, designer, electrician, plumber, tile or waterproofing professional, and installer identify unresolved questions before products are ordered or walls are closed.
1. Measure the finished steam enclosure
Record inside width, depth, and height at the finished tile or wall surface—not rough framing. Note any slope, dropped area, ledge, column, or full-height bench that changes the enclosed air volume. The Kohler selection guide defines base volume as width × height × depth and recommends a ceiling height of 8 feet or less. Kohler controller and steam-head selection guide, form 22-3187-0824 (official Kohler source)
Worked geometry example
A finished enclosure measuring 5 ft × 4 ft × 8 ft has a base volume of 160 cu ft. In Kohler's published sequence, 160 cu ft is above the 112-cu-ft K-32325-NA limit and within the 240-cu-ft K-32326-NA limit, before any ceiling-height step is considered. Official capacity table (official Kohler source)
2. Describe the enclosure and openings
- Identify which walls are solid, glass, or partly open.
- Record the door wall, hinge side, clear opening, and swing.
- Mark exterior walls, windows, skylights, and unusual transitions.
- Confirm that the design team has a continuous steam-rated enclosure, waterproofing, vapor-management, and drainage strategy.
SteamDesignPro records finish and envelope notes for professional review. It does not apply an invented material multiplier to Kohler's sizing table; the current Kohler selection guide bases the published selection procedure on room volume and ceiling height. Review the manufacturer procedure (official Kohler source)
3. Coordinate people, fixtures, and hot surfaces
Place the bench, door, shower fixture, control, and steam head as one coordinated composition. Preserve usable circulation and make the door swing legible. Treat any steam-head proximity warning as a prompt to consult the current product-specific installation guide. Kohler's current K-323xx generator instructions say not to locate the steam head near a seat or bench because it becomes hot during operation. Kohler installation instructions 1601844-2-B (official Kohler source)
A 3D view can expose obvious conflicts, but it cannot see blocking, piping, wiring, membrane laps, structural conditions, or required clearances concealed behind finished surfaces.
4. Review generator size and location together
First calculate base volume. Then apply the manufacturer's ceiling rule and confirm that the resulting model still covers the room's actual volume. Kohler says the generator should be installed within 25 feet of the steam head and requires a separate dedicated 240 V circuit. Tandem selections require two dedicated circuits and two drain pans. Kohler sizing and system notes (official Kohler source)
The guide also says no GFCI should be connected to that circuit. That is a manufacturer instruction, not permission to bypass current electrical code. Put the apparent requirement in the project record and have the licensed electrician reconcile the current installation manual, adopted code, and authority having jurisdiction before work begins.
See the full sizing method and model table.
5. Select a compatible control path
Begin with the shower system: mechanical, Anthem+, or DTV+ digital. For a mechanical shower, Kohler's guide lists K-5557, K-5558, or K-32312; K-32312 pairs with a separately sold K-32309 linear or K-32310 square steam head. For an Anthem+ or DTV+ digital shower, it lists K-5548-K1, K-5549-K1, or K-32311; K-32311 also pairs with the linear or square head. Tandem systems require two steam heads. Official controller compatibility chart (official Kohler source)
Finish availability varies by SKU, so verify the exact complete model number on the current product page at the time of specification rather than assuming every displayed finish is available for every component. Current Kohler Invigoration product results (official Kohler source)
6. Make the unresolved work explicit
Before handoff, save the dimensioned plan and list the assumptions that still need field verification. A strong preliminary package does not hide uncertainty; it assigns it.
- Designer or architect
- Enclosure geometry, door operation, accessibility, assemblies, and permit-document coordination.
- Waterproofing and tile team
- Steam-rated membrane system, transitions, penetrations, slope, and manufacturer-required details.
- Licensed electrician
- Load calculation, circuit and conductor design, disconnecting means, bonding, protection, permits, and code reconciliation.
- Licensed plumber and installer
- Water, steam, relief, drain, service access, commissioning, and all product-specific installation requirements.
Use the steam-shower checklist for the handoff meeting, and keep the source register with the project record.