Flush-o-meter

If your architect doesn't know for sure, odds are you're going to have problems bigger than this.

See the article on this from last year:
http://www.epa.gov/watersense/products/flushometer-valve-toilets.html
However, you can get "green" flushometer toilets now . See Kohler and American Standard for examples.

My contractor wants me to replace my old flushometer toilet with a tank style when I renovate my bathroom. He says that they're too noisy and have ugly pipes in the back. You can also place things on top of the tank.

I'd rather have the flushometer because the tanks needs adjustments and repairs from time to time. Also, sometimes you have to flush the tank toilets a few times to get the same result as with the flushometer. I've had no problems with my 1952 flushometer in the year I've been in this apartment.

Coming from the UK, where tank-style toilets are the norm, I would never choose one over the flushometer type. They are far superior.

Just looked at my Co-op Board's renovation rules: "New toilets must have gravity flush with no pressure assist devices. New flushometers are not permitted. " I'm gut renovating my bathroom and my old flushometer toilet is being moved. Board rules also say "No plumbing will project into or below the structural slab and no structural slabs will be channeled." So the architect is getting around that by putting in a rear discharge/rear outlet / back outlet toilet. This one:
ICERA
https://www.icerausa.com/sproduct.php?productID=35

NWT - I hear you. I think my architect just has a strong aversion to the "look" and is hoping that I will acquiesce! They seem on top of their game elsewhere.
jel - Thanks for the article. It sounds as if there are "greener" options available to use if you choose, but that it is not (yet) required. I would certainly have the plumbing checked out and tuned up, but I prefer to keep the current system. The noise doesn't bother me and I would only end up storing stuff I don't need on a tank!
I'm fine with the look given that it works perfectly and fits the prewar style that we are going for - subway tile on the walls, hex on the floor, nickel hardware etc. And yes, they are a NYC classic.
Propin - Nothing in my building's rules and I do know that there are plenty of units that still have them but thank you for the suggestion if the answer turns out to be "no more".

I am planning the same type of renovation. When the contractor grumbled, I asked him if he could find me a tank toilet then where the tank was mounted overhead and you pulled it with a chain. It ended the discussion on a humorous note.

Too much toilet talk on Streeteasy.

****DO NOT EVER REPLACE YOUR FLUSHOMETER!!!!!*****

If you do, you will regret it bitterly every waking day of your life.

I would be very careful. I am trying to sell a co-op unit, we have a closing date scheduled for this month, and the co-op board is suddenly preventing the sale because we do not have a low-water-use toilet, 1.6 gpf (also we lack Energy Star appliances).

This seems to be driven by NYC building codes, it's not something the co-op dreamed up, based on my very preliminary emergency research. It depends on the size of your building how stringent the phase in of the rules are.

The EPA says old flush o meters use 3.5 gpf, but some new ones are out that are even more efficient than the best tanks.

SO I would make sure it's low water use, whatever you do.

Argh - Preventing your closing? I could see them compelling the buyers to do something but the sellers? I know that my building is very energy efficiency aware (maybe some sort of tax credit when you meet a certain standard?) but they don't compel shareholders to purchase Energy Star rated appliances.
Good luck with the closing! Hope that this all turns out to be just a bump in the road for you.

The beauty of the flush-o-meter is that you're not limited to just 3.5 gallons per flush; you can just hold down that lever and just let it rip until that bowl is gleaming!!

New2me, how did this work out?