TOM'S TECH TIPS
CALGreen & ShowerSense
As you learned last month when that smarty-pants Derek tried to take my job (and/or kindly gave me a break, depending on how you look at it), a CALGreen-Compliant shower must have a total flow of no greater than 1.8 GPM per shower valve.
If you're designing a custom shower (i.e., multiple outlets in the shower), there are actually two ways to accomplish this. Pretty nifty, right?
One way is if the valve itself is flow-restricted to 1.8 GPM (like the GROHE SmartBox, when the flow limiter is installed), such that no matter how many shower outlets are running at the same time the total flow will still be 1.8 GPM. That is, if you're running two shower heads at the same time, each shower head will flow 0.9 GPM, and if you're running 57 shower heads at the same time, each shower head will flow approximately 0.032 GPM (not recommended). Of course, as far as I know, there are no shower valves on the market that can operate that many shower heads simultaneously. The highest number that I know of is only three, and that distinct honor belongs to the aforementioned GROHE SmartBox (cough humblebrag cough).
The second method for achieving a CALGreen-Compliant custom shower is to use a valve that only allows one shower outlet to run at any given time and all installed shower outlets flow no more than 1.8 GPM. An example of this method is a pressure balance valve paired with a discreet-function diverter, where the diverter has positive stops between each outlet.
See, I told you it was nifty!
To celebrate the new matte black finish that Steamist just introduced, I want to remind you of what is to me the niftiest way to accomplish method #2: the ShowerSense valve. The ShowerSense valve can be operated straight from the Total Sense digital control, and can be used even without a steam generator installed if your client doesn't want steam (as if). Either way, that means no matter how many shower outlets (within reason) and/or steam generators, lights, music, and aromas your shower design has, your client can operate everything from a single control on the wall. And how is it CALGreen compliant? Because Steamist planned ahead for the California market: the Total Sense control will only allow one shower outlet to flow at a time. Those clever Steamist people.
Thanks, Tom S