As a construction journalist, I am on seemingly every building material manufacturer’s mailing list. When a big trade show like the International Builders’ Show approaches, my inbox fills with promotional emails. Many, if not most, of the emails are about luxe products—fancy faucets, Corian countertops, high-end appliances, etc. I could not care less about these things, so I was surprised to discover my interest in an option from the Delta Faucet Company, which I learned about at this year’s IBS, where I did a little digging on behalf of GBA.
I was invited to preview their new Showersense, a customizable, Wi-Fi-enabled shower valve that looks like an iPhone and operates with touch control. It offers connectivity to virtual assistants, so I suppose you could order Alexa to turn the thing on. The gizmo had no appeal for me until Rachel Day, a Delta rep, segued into talking about the company’s new Steamscape Steam Shower, set to hit the market in summer 2023. It uses the same controller.
I imagined myself using the steam bath-shower combination and thought I would linger longer, luxuriating in the heat on a winter morning. I could even shave in the steam and, I imagined, waste additional gallons of water in the process. So, I asked, “How much water does it use for normal steaming?” It turns out that a 20-min. steam session uses less than 1 gal. of water. Suddenly, this indulgence might be given a green angle, as an average 10-min. shower with a standard shower head uses about 25 gal., according to the Environmental Protection Agency. My showers are never long, but I could spend 20 min. (or more) in a private spa.
Other concerns I raised with the Delta rep were not addressed as readily. They included the handling of the extra bathroom humidity and the energy consumed by the steam generator.
Delta got back to me by email to say they size steam-generating units by cubic feet, and they sent me a table of sizes. The most practical is the 7.5KW unit, which can supply steam to a shower measuring 250 cu. ft. (5 ft. by 6 ft. by 8 ft. tall is 160 cu. ft.). The company advises upgrading the bathroom supply lines from the standard 1/2 in. “We recommend 3/4-in. supply lines to ensure an adequate water supply to your generator. As with other models, 1/2 in. will suffice, but this increases the potential for additional system noise. To avoid this, we recommend the larger diameter,” explained Delta spokesperson Allyson Brunner. Their steam shower units start at $2100.
Kohler makes a steam shower too
The Kohler steam generator also consumes about 1 gal. in 20 min. It will operate as a standalone with their steam-only “Invigoration Controller” or paired with the company’s digital interface DTV+ system that also controls their luxury, multi-function shower.
Huston Sprang, senior product manager at Kohler, explained, “The ideal height for a steam shower is 8 ft., so if a user goes above that height, the steam generator size needs to increase.” According to Sprang, a 4 ft. by 5 ft. shower 8 ft. high will pair well with a 9kW steam generator consuming 60 AMPS, or about 4.8KW during 20 min.—a little less than a dollar in Texas.
When I installed a Kohler digital shower system last year, I had to upgrade my supply lines from 1/2 in. to 1 in., almost like a lawn sprinkler system. So, I questioned the steam unit. “There isn’t special plumbing needed,” said Sprang, “but we require 90° copper fittings to supply the generator. For optimum performance, the steam generator must be installed within 25 ft. of the steam head. To ensure proper operation, we recommend water supply be tested before operating the steam generator to ensure a Hardness of 60 ppm (3.4 gpg) max with a Total Alkalinity of 150 ppm (8.8 gpg).”
When I asked Sprang about the cost of Kohler’s steam shower all in, he said, “There’s a wide range as our 5kW list price is $3,023.85 to our 30kW runs $9,584.05. Then the controller price can vary depending on whether you use the steam-only controller or DTV+. For example, if a user selected a 9kW generator and the steam-only controller, the list price would be $4,530.95. This would include the generator, controller, and a round steam head.”
Although neither Delta nor Kohler specify the bathroom exhaust fan, it seems evident that with a steam source, you will need a high-quality unit, preferably with a humidistat, to clear any excess water vapor that might escape the enclosure. SteamSaunaBath suggests fans made for home steam rooms. The supplier recommends the Bathology brand, including several models installed outside the steam enclosure and the Atmospheric 410 steam shower exhaust installed inside the steam bath. Prices range from $508 to $2336.
Luxury is rarely compatible with conservation— consider the electric GMC Hummer or 10,000-sq.-ft. net-zero homes of the very wealthy. But a steam shower that consumes 1 gal. of water seems like a temperate indulgence, if you can afford it. I cannot, but I admit I’d like to have one for when the weather is brisk, and a long, warm—guilt-free—steam bath would feel good.
Fernando Pagés Ruiz is a builder and an ICC-certified residential building inspector active in code development.
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