Are you doing a remodel? The CalGREEN code for 1.8 gpm only applies to newly-constructed buildings. I think everyone else is subject to the 2010 California Plumbing Code 402.1.2 which specifies 2.2 gpm.

Your local code may be more strict though.

No, not new construction. I'm in L.A., but I thought that the Sensate was only available in the 1.8.

The salesman at Fergusson told me that that's what they were selling. I guess I could buy one from out of state online.

The standard model works at 1.8 gpm flow rate. There is an optional accessory you can buy which increases the flow rate to 2.2 gpm.

Aha! Thank you, I saw it listed, but it appeared grayed out. I assumed that meant that it was unavailable for that faucet. Where did you see the option? Was it from a vendor?

I saw it on the Kohler spec sheet. You might want to call Kohler directly to order the high flow kit & make sure it is compatible.

Kohler Spec Sheet