Which floor are we on anyway?

There are 32 steps from the ground floor up to our apartment on the 1st floor (what would be the 2nd floor back home). There is a small elevator that fits about 2 people (or one person with a suitcase) but it is slow so we rarely use it. If you push the button labeled "1" on the elevator control panel, you go to the floor above us. For our floor we push "ES" instead. I haven't figured out what that stands for. (some help here!) "RC" stands for rez de chaussee which means ground floor.