Updated July 5, 2026 · 8 min read
A steam shower is a standard shower enclosure built to hold steam — sealed, sloped, and paired with a dedicated generator — rather than a separate fixture. Because it starts from a shower you'd likely be building anyway, the honest way to think about cost is what the steam system adds on top, not a total project price in isolation.
This guide gathers cited 2025–2026 figures from This Old House, Fixr, and Bob Vila for installed cost, plus manufacturer sizing guidance from Steamist and Mr. Steam for how a generator is sized to your enclosure. Boise Bath doesn't publish a standalone steam shower line item — it's an upgrade layered onto a walk-in shower build — so we show what the national data says that upgrade typically costs.
Key takeaways
- Fixr (2025) prices steam shower installation nationally at $8,000–$15,000 (average $11,000); This Old House and Bob Vila put simpler prefab-weighted averages closer to $4,300.
- Prefab vs. custom is the main cost split: $2,800–$6,200 prefab vs. $4,000–$10,000 custom, installed (Fixr, 2025).
- The generator itself runs roughly $500–$4,000 depending on the size needed for your enclosure (Bob Vila 2023, Fixr 2025, Mr. Steam 2022).
- Generators are sized by adjusted cubic footage — stone and marble need roughly double the capacity of ceramic tile for the same enclosure size (Steamist).
- Boise Bath doesn't publish a standalone steam shower rate — it's an upgrade added to a Walk-In / Custom Tile Shower build, published at $12,000–$22,000.
The short answer
Fixr (2025) prices steam shower installation nationally at $8,000–$15,000, averaging $11,000, with a full range of $3,800–$25,000. This Old House and Bob Vila both put the average somewhat lower, at roughly $4,300–$4,325, with a typical range around $2,800–$7,100 — these figures appear to weight toward simpler prefab installations, while Fixr's range captures more custom and combo builds.
As with the other guides in this series, the split that predicts your total is prefab versus custom, and whether the steam shower is paired with a tub, sauna, or jetted feature.
Cost by installation type
Fixr (2025) breaks steam shower installation into prefab and custom tiers, both installed.
| Installation type | Installed cost |
|---|---|
| Prefab steam shower | $2,800–$6,200 |
| Custom steam shower | $4,000–$10,000 |
| Prefab steam shower + tub combo | $4,000–$7,000 |
| Custom steam shower + tub combo | $6,000–$12,000 |
Source: Fixr (2025). Labor alone for a 36"×48" shower runs $500–$780 (prefab) or $3,000–$6,000 (custom), per the same source.
The steam generator
The generator is the component that turns a standard shower into a steam shower, and its price scales with the room's cubic footage. Bob Vila (2023) prices a generator at $500–$2,000; Fixr (2025) prices the same component at $400–$4,000 for larger enclosures. Mr. Steam's own 2022 pricing shows how that scales by unit: a generator sized for up to 71 cubic feet runs about $2,175, while one sized for 162–257 cubic feet runs about $3,350 — with an entry-level unit for a non-porous-wall enclosure starting around $1,550 before installation.
Mr. Steam (2022) also frames the upgrade in whole-project terms: a sample 120-square-foot bathroom priced at $24,000 without a steam feature came to $30,595 with one added — roughly a 20–35% premium over a standard shower build, which lines up with Mr. Steam's general guidance for the size of the upgrade.
Sizing the generator to your shower
Steam generators are sized to "adjusted cubic footage" — the enclosure's raw volume multiplied by a factor for its surface material — per Steamist's manufacturer sizing guide. Getting this right matters for cost: an undersized generator won't hold steam, and an oversized one is money spent for no benefit.
- Base calculation: length × width × height of the enclosure, in feet (Steamist)
- Material multiplier: natural stone or marble ×2.0; ceramic, porcelain tile, or glass block ×1.35 (Steamist)
- Exterior wall adjustment: one exterior wall ×1.1, two exterior walls ×1.2 (Steamist)
- Ceiling height adjustment: 9 ft ceiling ×1.15, 10 ft ceiling ×1.3; ceilings should not exceed 8 ft as a rule of thumb, 10 ft as an absolute maximum (Steamist)
- A typical 4×5×8 ft (160 cubic foot) ceramic-tiled stall needs at least a 7 kW generator; a stone-tiled stall of the same size needs roughly double that capacity (This Old House)
| Generator size | Adjusted cubic footage range |
|---|---|
| 7.5 kW | 101–250 |
| 10 kW | 251–450 |
| 12 kW | 451–550 |
| 15 kW | 551–675 |
Source: Steamist steam generator sizing guide (manufacturer). Consult a licensed installer to confirm sizing and electrical requirements (typically 220–240V) for your enclosure.
What Boise Bath publishes
Boise Bath doesn't publish a standalone rate for a steam shower — it's offered as an upgrade to a Walk-In / Custom Tile Shower, which is published at $12,000–$22,000. Based on the national data above, expect the steam system itself (generator, controls, and the extra sealing and sloping a steam enclosure requires) to add somewhere in the low thousands to roughly $10,000 on top of that base shower cost, depending on enclosure size and whether you choose stone or tile. For the full underlying shower build cost, see our walk-in shower cost guide and our Boise bathroom remodel cost guide.
Because a steam shower must be fully sealed to trap steam, waterproofing is not optional the way it can be debated on a standard shower. This Old House recommends 6-mil plastic sheeting with one-foot minimum overlaps, or two coats of liquid polymer membrane (or a polyethylene sheet membrane) behind stone or tile, with stone sealant reapplied roughly every two years.
3-year workmanship warranty
Every steam shower we install is backed by a 3-year workmanship warranty on our construction, in addition to the manufacturer warranty on the steam generator itself.
Frequently asked questions
- How much does a steam shower cost in Boise?
- Boise Bath doesn't publish a standalone steam shower rate — it's offered as an upgrade to a Walk-In / Custom Tile Shower build, published at $12,000–$22,000. For the steam system itself, Fixr (2025) prices national installation at $8,000–$15,000 (average $11,000) for a full steam shower, while the generator component alone runs roughly $500–$4,000 depending on size (Bob Vila 2023, Fixr 2025).
- What size steam generator do I need?
- It depends on your enclosure's adjusted cubic footage — its raw volume (length × width × height) multiplied by a factor for its surface material. Steamist's sizing guide multiplies by 1.35 for ceramic or porcelain tile and by 2.0 for natural stone or marble, then adds further adjustments for exterior walls and ceiling height above 8 feet. A typical 160-cubic-foot ceramic stall needs at least a 7 kW generator, per This Old House.
- Does a steam shower cost a lot more than a regular shower?
- Not necessarily as much as people expect. Mr. Steam's own cost comparison shows a sample 120-square-foot bathroom running $24,000 without a steam feature versus $30,595 with one added — roughly a 20–35% premium over a standard shower for the generator, controls, and the extra sealing and sloping a steam enclosure requires.
Sources
- This Old House — All About Steam Showers: How They Work, Cost and Installation
- Fixr — Steam Shower Installation Cost (2025)
- Bob Vila — How Much Does a Steam Shower Cost to Install? (2023)
- Steamist — Steam Generator Sizing Guide (manufacturer)
- Mr. Steam — How to Estimate the Price of Installing a Steam Shower
Claims and figures are drawn from the sources above and provided for general guidance; your project may vary. Photography is illustrative of design concepts. For a fixed price on your specific bathroom, request a free estimate.
