I had never even heard of these until yesterday, but they look interesting.  The American Standard model I looked at was single-flush, 1.1 gpf.

For those who aren't familiar (like I wasn't), here's how they work -

Inside the tank is an air-filled bladder, with a specific volume of air.  As the tank fills around this bladder, it compresses it, increasing the pressure inside the tank.  When you flush, rather than just gravity, the air pressure of the bladder forces the water into the bowl.

I've read some reviews, mostly positive.  The one negative I've seen is that they are noisier than a "normal" toilet.  I have read that older models were very loud but current models are significantly quieter.

The prices seemed fairly in line with a quality low volume or dual flush - these seem like they could be a good option...

If you install a Toto Drake, you will have dual flush capability and great performance. We replaced our 'crappy' American Standard 2092 with Toto and could not be happier! At least not happier with a toilet:)

I also switched to Toto. I've used pressurized ones - they are loud. I also wonder, if one wants a pressurized toilet, why not just go with a commercial type (eg, Sloan Flushometer)? Then you can put a pressure tank elsewhere (nice clean look).

I have a lot of experience with toilets. I have 5 kids and a housekeeper and lets just say we need stellar performance. I have replaced four toilets in my house. The first was when I was naive and thought a good brand meant a good toilet and bought a Kohler that looked nice. Mistake as we still get clogs in that toilet.

Next I bought a Toto and although not bad, it does not have a forceful flush. For the next toilet I really researched and looked at the studies that rate toilets. I chose a Kohler pressure assist and then also got a Gerber pressure assist for the last bathroom that we remodeled. These two toilets are the best. You will probably never have a clog, which was my main priority. In addition, the water level and area in the bowl is very good and that means the bowl hardly ever gets dirty. If it does get a little dirty I just flush again and usually that cleans it out. I also bought a Gerber pressure assist for a rental property and that was a water saver (delivered by mistake) and I have never had a clog in that either. These 3 had the Sloan flushmate contraption inside, as I think some of the Gerbers now have their own brand pressure assist in the tank.

In any event, when it comes to toilets I would not try to save water and I don't go for the 1.1 gallon and rather keep my toilet cleaner and have better performance with more water. The two I have in my home are the 1.6 gallon models.

Now the only downside I can see to these toilets if it bothers you is that they are noisier and my guests have gotten startled and one even reported "he was afraid his privates were going to get sucked down" that's how powerful they flush. I personally rather take the noise of the flush rather than hearing my husband curse because the toilet is clogged for the twentieth time.

The Kohler we have is one of those taller ones and I am short (5'1") and prefer the standard height so just make sure you are aware of the toilet height you are getting.

Lastly, the Sloan Flushmate part in the tank is guaranteed for ten years I think after that it is not a big deal to replace that part in case it breaks.
The cost of these toilets is really reasonable at around $350 if I recall. For that price, you never will have to call a plumber and will have peace at home. If you would like to read the Canandian ratings yourself, let me know and I will try to find the link somewhere. It does not come up so easily on the search engines, but that study is frequently updated and lists every brand and model and tells exactly how many grams each can flush. Let me know if you have any more questions.
To sum up, pressure assist is definitely the way to go!

I agree with all of that. A Toto is good for most uses, pressurized is stronger (but noisier). Maybe they need to build the ultimate - a dual flush, one button pressurized, the other not.

I'd rather have any guests hear a whoosh rather than a "go baby go" chant from the bathroom. Next house will have these and a urinal for the bathroom off the entertaining area in lower level.

Posted By jerkylips on 12 Jan 2010 08:52 AM

...Inside the tank is an air-filled bladder, with a specific volume of air.  As the tank fills around this bladder, it compresses it, increasing the pressure inside the tank.  When you flush, rather than just gravity, the air pressure of the bladder forces the water into the bowl...

"Bladder" typically connotes an expandable balloon or sack like container and in that regard, it's a potentially confusing term when discussing pressure-assist toilets.

An air-inducer valve on the pressure-tank itself (typically made from a hardened material such as ABS, polypropylene, etc.) draws-in air as the tank fills with water. As the water level rises, the air that's been drawn-in during the fill-cycle is compressed. When the internal pressure reaches that of the system's factory-set regulator, the tank is pressurized and ready to flush.

When actuated, the compressed air does vigorously push the water through the toilet and teh waste into the drain-line instead of "pulling" the waste with a syphon like a gravity toilet.

The actual volume of air isn’t based on a fixed bladder size but on the water flow-rate into the system. That’s why pressure-assist toilets always have a specified minimum supply-line pressure; insufficient pressure will not draw enough air to fully pressurize the system and performance suffers.

I hope this clarification is helpful to everyone.

I've had the Sloan type, and they were LOUD.  Worse still, one of them, on the opposite side of the wall was a bedroom where the bed backs into, and everytime it flushes it's loud enough to wake up a sleeper.  And you can pretty much hear it throughout the house (although the house wasn't that large).

If you're concerend with water usage and flushing performance, there are some dual flush and even some single flush 1.28Gal units on the market that have a MAP score attached to it, and the higher the MAP, the higher the performance, with the testing being done using soybean paste cased in latex to simulate, well, you know...

Here's a fairly recent report:  http://www.a4we.org/uploadedFiles/R...20.pdf

Some of them can handle up to 1000g (20x50g) which is the maximum they will test at, so it'll take a hell of a lot to crap out that much... 

We picked up 5 of the Price Pfister Treviso's for our nearly complete project for under $200/ea that did 3L/6L and had a MAP score of 1000, so I'm hoping these will have the flushing performance without the loud WOOOOSHHHH...

Victor
www.ecobuilthome.ca
A 4350sqft Net Zero Energy initiative

Great posts in this thread.

I'd stumbled on an earlier (5th edition) MAP score report, which tested up to 1100. ANyone know why the more recent one (15th edition) stops at 1000?

Last time our master bath was snaked, the plumber used a video camera and found an area of the drain line that was problematic -- there is always water standing there, and material can get caught at that spot. Given this, would a high-performance gravity toilet (say, any of the ones that scored 1100 in the 5th edition MAP and 1000 in the 15th edition) work, or would the drain issue mean only a pressure-assist will reliably work?

We have the Kohler Cimarron Comfort Height elongated toilet 1.28 gal, and are very impressed with its performance. It is a regular gravity toilet and not loud at all.

-Rosalinda

Jetlad...silly question...but, why not repair the drain so it slopes properly? Sh*t likes to go downhill.
If you go with a quiet and cheaper gravity toilet pay attention to the size of the flapper...... Larger flapper= better flush!

Posted By surviverguy on 24 Mar 2012 05:41 AM
Jetlad...silly question...but, why not repair the drain so it slopes properly? Sh*t likes to go downhill.
If you go with a quiet and cheaper gravity toilet pay attention to the size of the flapper...... Larger flapper= better flush!

We're not eager to have the floor ripped up in the upstairs bath, I'm sure it'd be a lot of work, no telling how much of the area would have to be removed (toilet, shower, maybe tub and one or both sinks). When the time comes to remodel it, that would be a great opportunity to fix the plumbing. We ended up getting an American Standard Champion 4, which has a 4" flap valve and a MAP rating of 1,000. I think we'd have been better off with a power-assist rather than gravity, but I was scared it would be too noisy. I was thinking that a dual-flush that used gravity for the small flush and power-assist for the large flush would be an ideal way to go, but couldn't find such a thing, and maybe the too modes are fundamentally incompatible so it can't be done.

As a facilities technician in charge of plumbing at a large corporation,  I have alot of experience with toilets(we have close too 100 toilets of various types in several different buildings), I can tell you that the pressure assisted toilets do a great job and are not nearly as noisy as one might think.  If you want to use a gravity feed, don't buy the $100 toilet.  The $200 toilet really is twice the toilet.  This one of the times where you really will get what you pay for.  If you can afford it make sure it is a 4".  You can dump a bucket of golf bals down there and not clog it.  Pressure assisted will cost more but it does a better job with less water.  Hope this helps.

Jetlad....

Adding a better toilet will not cure a low spot, and they only get worse.  You really need to find out why you have the lowspot and deal with it accordingly.

If I ever upgraded, I'd probably go with a commercial tankless toilet (with a pressure tank hidden away somewhere).

You can dump a bucket of golf bals down there and not clog it.

I have yet to find a golf ball in there after using the toilet. I suppose there is always a first time.....

Posted By Ronscott64 on 14 Jun 2012 12:32 PM
As a facilities technician in charge of plumbing at a large corporation,  I have alot of experience with toilets(we have close too 100 toilets of various types in several different buildings), I can tell you that the pressure assisted toilets do a great job and are not nearly as noisy as one might think. 

Thanks very much for the reply, Ron. We replaced the Toto Drake with an American Standard 4" that got a top MAP score (Toto also has these, but they weren't in stock at our local Home Depot). It's much better, with only an occasional clog. Pressure assisted would likely be better, but we were concerned about noise.

Posted By Ronscott64 on 14 Jun 2012 12:32 PM
Jetlad....

Adding a better toilet will not cure a low spot, and they only get worse.  You really need to find out why you have the lowspot and deal with it accordingly.

We're just hoping to avoid ripping up the floor and maybe the tub as well.