Two-level / back row seating in a home theater

Currently I can have only one row of seating on the couches that comfortably seats seven people, everyone else has to sit on the floor. I am considering building a raised platform for rear seating so that I can have two rows of couch seating.

For those of you that have two-level seating in your home theater, how much higher is the back row flooring than that of the front row?

The rear riser is 14" tall. Thus one step up at 7" to the platform. This also allows you to see over the heads of the front row while in reclined position.

Make certain to reinforce the risers, and fill with insulation. Otherwise you will have a very large resonance chamber...

Good luck.
Wow Audiofankj! What a nice theater you've got there! Jeez...your chairs are insane. Sitting in those things would even make watching an awful movie enjoyable.

My theater is not a dedicated theater, it is also my living room. The seating on the risers will actually be couches. I'm working with a guy to build me a mobile riser that can be rolld out of the way once the screen is rolled up into the ceiling and the projector is put away ....don't even ask, it's too convoluted to explain here, but the design and concept is pretty ingenious.

..thanks for your suggestions, I appreciate it.

Actually, a lot depends on where you have the monitor (pj screen) mounted. If it's higher on the wall, you can get away with a lower back riser. If your monitor is down near the ground, or lower, you will need to build a higher riser.
See Russ Herschelmann's "riser" articles of old. That should help clarify.
Actually, you can search building a riser DIY by googling, it, like anything else.
good luck
Hey Mitch after looking at your screen I just want to add what you probably already know. When adding a second row make sure the bottom of screen is not too low as folks in rear seats will not be able to see bottom if its less than 25-30 inches from floor.....your screen goes to the floor so I just wanted to add that caution, cheers.