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A two piece toilet has several advantages over one piece toilets. They are generally more affordable and will require less heavy lifting when it comes to installing them. But that doesn't mean they are perfect for everyone. In fact, there are several drawbacks. The reality is all about finding the right balance between your bathroom and budget requirements.
We aim to help you with this in our detailed buying guide below. We'll be covering the basics, such as the pros and cons of buying one, along with the more advanced stuff, such as analyzing individual products specifications.
The Drake II is one of our favorite ranges. It also ranks 2nd in our best overall list. Our reasoning behind this is simple, it's double cyclone flush is effective, achieving a 800g MaP score. What makes it even more impressive is that it only uses 1.28 gallons in doing so.
It complies with the Americans with Disabilities Act, making it more accessible, and the bowl is elongated for improved comfort and seated support.
We would describe this as a great all round solution for the home, that is designed to handle large quantities of waste without clogging up.
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| TOTO Drake II | KOHLER Tresham | TOTO Promenade | KOHLER Memoirs | American Standard Cadet 3 |
Mansfield Summit | |
| Model number | CST454CEFG | K-3950 | CST423SF#01 | K-6669 | 2989.101.020 | 388.387.WHT |
| Rough in | 12" | 12" | 12" | 12" | 12" | 12" |
| Flush type | Double Cyclone | AquaPiston | G-Max | AquaPiston | HET | HET |
| Touchless | ||||||
| Trip lever | . | |||||
| Button | ||||||
| GPF | 1.28 | 1.28 | 1.6 | 1.28 | 1.28 | 1.28 |
| WaterSense | ||||||
| MaP | 800g | 1000g | N/A | 1000g | 1000g | 1000g |
| ADA | . | |||||
Rim height
Height without seat
|
16-1/8" | 16-1/2" | 16-1/8" | 16-1/2" | 16-1/2" | 16-1/2" |
| Elongated | ||||||
| Round | ||||||
| Square | ||||||
WSA
Water surface area
|
7-1/8" x 9-1/8" | 11-1/2" x 9" | 8-7/8" x 6-3/8" | 11-1/8" x 8-1/2" | 9 x 8" | 8 x 9" |
Water level
Rim to surface |
5-1/2" | 5-3/8" | 5-7/8" | 5-3/8" | N/A | N/A |
| Dimensions | 28.8 x 16.5 x 29.4" | 28.5 x 16.5 x 14.5" | 26.1 x 18.5 x 33.4" | 31.4 x 28.2 x 20.1" | 30.2 x 15.8 x 30.2" | 27.5 x 19.4 x 32.5" |
| Weight | 94 lbs | 72.8 lbs | 86 lbs | 101 lbs | 110 lbs | 80 lbs |
| Trap size | 2-1/8" | 2-1/8" | 2-1/8" | 2" | 2-1/8" | 2" |
| Flush valve | 3" | 3" | 3" | 2" | 3" | 3" |
| Concealed trap | ||||||
| Skirted | ||||||
| Intelligent | ||||||
| Floor mount | . | |||||
| Wall mounted | ||||||
| Colors | Cotton, Beige, Bone | White, Biscuit, Bone | Cotton white, Bone | White, Sandbar, Black | White | White |
| Seat | ||||||
| Soft close | ||||||
| Bidet | ||||||
| Supply | ||||||
| Rating | 86% | 86% | 85% | 84% | 84% | 81% |
Questions relating to the main differences between one and two piece units are very common. We break down the most important information below.
Installation
Because the tank and bowl are shipped separately and don't come attached to each other, you could make an argument that they are lighter to lift up and move into position, removing the heavy lifting and perhaps making what could of been a two man job, a one man job.
However, the other side of that argument is that there will be extra work involved in attaching the bowl and tank together, making the installation process more time consuming and tiring.
Cost
Two piece units are typically more affordable than one piece. The same applies to replacements and upgrades. Lets say your tank breaks, with a single piece product, you would have to buy a brand new toilet in full. With a two piece, you would only need to replace the broken parts (the tank in this case) which can be significantly cheaper.
Durability
It's hard to say which style would be more durable without knowing the brand and components inside. But because some plumbing fixtures are exposed in the tank gap, there is a bigger risk of leaking or damage in that specific area. One piece units don't have this problem because they're seamless.
Cleaning
For a toilet to be easy to clean, there needs to be a limited or reduced amount of gaps or indents where germs and bacteria could hide. On average, one piece units will have the upper hand here as there will never be that gap between the tank and bowl for bacteria to thrive. That gap can be hard to wash.
There are some things that can help improve the cleaning situation though. For example, getting a seat that has a quick release feature will allow you to easily wash beneath the seat and its surrounding area without needing to get the toolbox out. Alternatively, you could choose to get a skirted exterior. While this doesn't solve the problems that arise from trhe gap, it makes the outside of the bowl a lot smoother and easier to clean.
The Drake II is made by Toto, one of our favorite brands, known for their reliability and performance. The CST454CEFG utilizes gravity alongside a double cyclone system to flush out the bowl. The power at which it does so is also impressive, scoring 800 grams on MaP. This is at the higher end of their scale, 1000 grams being the maximum.
Interestingly enough, it only uses 1.28 gallons per flush, which may come as a surprise as many people tend to associate performance with a high flowing rate. The 1.28 GPF figure given is WaterSense compliant, meeting strict EPA guidelines on saving water in the bathroom. You can expect to save many thousands of gallons over the course of its lifetime, saving you money in the process. We break this down into simpler terms on our calculator.
The bowl is elongated, right height, and ADA compliant. In terms of user comfort, there isn't many better combinations. The elongated shape gives better leg support, while the right height spec makes it easier to sit down and stand up.
You'll be able to find it in a number of different colors. A cotton white tends to be the most obvious choice for many. But there are also Beige and Bone as suitable alternatives that can help you match a certain theme.
The seat isn't included, so we recommend going for the SS224, SS214, SS204, or SS114 soft closing seats. Not every manufacturer excludes the seat, so that's something you'll need to consider and budget for.
The Tresham is another option which we rate highly. You can usually expect quality when it comes to buying something from Kohler. They are a big name with a solid reputation in the industry. The majority of their bathroom hardware is well received, with consumers leaving plenty of positive feedback about them. The K-3950 is no different.
We believe this is down to their powerful flushing system, which utilizes AquaPiston technology to let water pour three hundred and sixty degrees through the bowl, reducing the chances of missing a spot. To give readers an idea of the level of performance to expect, this is marked as 1000 grams on the MaP scale. That's the highest score you can get in bulk waste management.
Because it's effective in clearing the bowl out in one flush, shoppers will no doubt be under the impression that it is quite wasteful with water. When actually, this is WaterSense certified, using a low flowing 1.28 GPF. This makes it an economically viable option for your house.
You can expect the bowl to be taller than average sized bowls, measuring 16-1/2 inches from the base to the rim, making it both ADA compliant, accessible, and comfort height with the seating attached. However, you shall need to purchase the seat separately as it doesn't come with it. This seat will need to be elongated to match the bowl shape. The K-4636 Cachet Quiet-Close, K-5588 Purefresh, and K-4108 C3 are all suitable options. You'll also need to buy the supply line separately. Make sure you plan ahead for all these upsells so you don't go over budget.
It is finished in a number of colors, white, bone, and biscuit among them. There is a generous water surface size of 11-1/2" by 9", and a water level from the rim of 5-3/8". Overall, we're of the opinion that this is a stylish toilet with a excellent set of features that are designed for residential usage.
As mentioned previously, This is a company that builds quite a number of products that stand out from the crowd. So where does the CST423SF#01 fall in this list? Does it hold its own against the market leaders? Find out below.
It uses Toto's G-Max system. This is a technology which combines a three inch flush valve with an extra large siphonic jet and wide water surface area. These three things combined create a powerful flushing action. However, it's not quite as efficient as the two above, but still consumes far less water than older 3.5 and 5.0 gallon tanks. The 1.6 GPF flow rate will work well with the SanaGloss glazing which stops waste from sticking to the bowl.
The elongated bowl will fit a twelve inch rough in measurement, and is right height, giving consumers with disabilities better access. The height to the rim alone is 16-1/8 inches, add a seat on top of this (which needs to be purchased separately) and it will measure in the comfort height range of 17 to 19 inches.
Its full dimensions are listed as 26.1 by 18.5 by 33.4 inches, and it has a trap size of 2-1/8 inches. You also get a fairly large water spot for keeping odors down and reducing the amount of streak marks.
We've analyzed the Memoirs product range in several of our other buying guides. Each time, we've highlighted its environmentally and eco friendly nature. A very efficient 1.28 gallon flush will help people save money on their home utility bills over time. This is an overlooked benefit that may even pay off all of, or at least part of the cost of the toilet over its lifetime.
If you shop around, you'll be able to find it in both traditional lighter colors, and some unique and unusual ones. White, Sandbar, Black are just a few examples. Couple this with its concealed trapway design and it gains a lot of points visually.
Similar to the K-3950, THE k-6669 demonstrates its ability to remove larger volumes of waste through the trap and outlet in the MaP scoring system. It achieves a 1000 gram score, which is the maximum you can get. All this makes the amount of water used seem even more impressive.
Like the others, it measures around the 16 inch mark to the bowls rim. 16-1/2 inches to be precise. With the addition of a seat, which incidentally is included, the bowl height will fall into the universal height category. The bowl is made in a comfortable elongated shape too, which provides more support and space.
The Cadet 3 is manufactured by American Standard. This is another popular brand name which produces a number of different types of bathroom hardware. This collection has a lot of good things going for it. Lets explore the specs below, and see how it could benefit you.
Like many of its competitors, the 2989.101.020 achieves a strong flush with lower volumes of water. A 1000g score, while using up to twenty percent less water than standard units.
The bowl offers a interesting seamless style, hiding the trapway outline and having smooth, easy to clean edges that look nice. It once again makes use of an elongated shape, which has several advantages over its round counterparts, the primary one being user comfort.
The rough in size you'll require to fit this is twelve inches, and the overall size is 30.2 by 15.8 by 30.2". It's equipped with a 2-1/8" trapway size and a 3" flush valve.
If you're searching for something with a contemporary theme that saves water, this model is worth consideration.
The Summit is made by Mansfield, a manufacturer which produces some very affordable sanitary ware. But how does the 388.387.WHT compare to our other picks?
The bowl has a rounded front, which is generally seen as a better alternative to elongated ones if you're lacking floor space in your bathroom. The compact nature of this design certainly has its advantages.
It's compliant with the Americans With Disabilities Act, and is also SmartHeight, which is really Mansfields way of telling us it's chair height, adding a few inches to the bowl. This helps people with disabilities, tall people, and the elderly sit down on the seat with less stress on the joints.
The surface on the bowl is coated in a ceramic glazing known as PuraClean, this makes washing and maintenance simpler and less time consuming as it helps prevent staining and dirt sticking to the bowl. Other companies have similar products to this type of glazing, and can be known as SanaGloss, Everclean, and WonderGliss. They're all designed to do a similar job.
It's 1.28 gallon flush (4.86 lpf) consumes far less water than 1.6 / 3.5 / 5.0 gallon units. Over the years this can help you save money on household bills too. And because it meets EPA WaterSense standards, you could be entitled to rebates depending on the state you reside.
Installing it should be quicker too thanks to its SmartFasten 3-bolt system.
Elongated or round? - Questions regarding the bowls shape is quite common. Their is no definitive answer for this. It's almost entirely dependent on individual users needs. As a general rule, round shape bowls are smart choices for small bathrooms. They tend to be shorter in depth (around 24" through to 26"), and leave more room in front. On the other hand, elongated shape bowls are a sensible choice if you're looking for strong support beneath your legs with plenty of space available. They are more suitable for the male anatomy too.
Comfort or standard? - The comfort label is a label given to bowls which exceed a certain height (17 inches in this case). There doesn't seem to be a uniform name given to this style of bowl. Comfort height is probably the most popular, but you'll also see them labelled as chair height, universal height, and a number of others. It changes from brand to brand. But what are the advantages to owning one of these over a standard sized bowl? To start with, there is a reduced distance in which you need to bend down. These extra inches can take a lot of stress off your joints which is why they often meet ADA criteria too. Secondly, they are an obvious choice for taller people, their seated positioning will be natural for them compared to standard ones.
MaP ratings - Maximum Performance (also known as MaP), is a useful scoring system which give consumers a chance to explore how well specific makes and models handle waste. How does this work? Well, products are sent to MaP, who are a third party company, for testing purposes. They put pellets or paste in the bowl to replicate waste and give each toilet a score based on how well they remove them from the bowl. Its not a perfect system, but it is a great tool for understanding how powerful a particular flushing mechanism is. 1000 grams is the absolute maximum score that can be achieved, with 0 grams being the worst. We recommend checking these scores for yourself, and try to stick with products which score at least 500 grams. At least that way you'll no it's less likely to clog up.
Waste outlet - Think about where you need your waste water to exit. Wheres the existing outlet? Does it need to be going through the floor, using the force of gravity, or through the back, utilizing compressed air to clean the bowl? There is no right answer to this, as it depends on your current plumbing situation. Air assist options tend to have a more forceful flush, but they can get quite noisy. Gravity fed units are easy to install in comparison, and will usually fit your average residential homes outlet without any extra renovation work.
Water spot - The water spot is a necessary odor fighting feature that also helps prevent the staining and streaking within the bowl. Larger water surface areas are usually the better option if you want to keep smells down. But be careful, if you choose a water surface too large, the water level rises too close to the rim. This is where splashing becomes a problem.
Floor or wall mounted? - There are two main reasons behind opting to install a floating toilet over a floor mounted one. The primary reason is that they are really good at saving space. The flexible design gives people more choice in where they fit it. In most cases the tank is hidden behind a wall with a carrier system. This creates the illusion of the bathroom being more spacious. The second reason is related to aesthetics. Lets face it, the way they are fitted gives them a unique advantage visually.
Water usage - If you're looking to get a toilet that conserves water, you should be looking at products labelled 'low flow' or 'WaterSense'. Both of these terms indicate that their flushing mechanisms are specially designed to use less water than older, inefficient units.
Rough in - The three main rough in sizes are as follows: 10", 12", and 14". The wide majority of households will require something that fits 12". But this is something you shouldn't be cutting corners on, looking for a short cut. You really need to know what your rough in is and measure it accurately. There is a in depth guide on how to do this on our home page. In simple terms, your rough in is the distance from your wall to the center of the waste outlet. It's not always a deal breaker if you get yours wrong, but it may result in there being larger than desired spaces behind the tank or sitting very close to your wall. The UniFit attachment gives you a bit more flexibility in this regard.
Consumer feedback - Buyers remorse can be a familiar feeling when purchasing expensive sanitary ware. But there are plenty of ways to avoid such feelings. The first is through having a basic understanding of the products specifications and functions. We cover most of this on our site. The second is through customer reviews. Take a look at what real buyers are saying about their purchases. This can help you identify the negative aspects of a product early, allowing you to focus your attention on a different one. The big online shops and forums are good places to start this research.
We've outlined several ways in which two piece toilets can be beneficial to you above. The products we've chosen made the list thanks to their strong flushing performance, ability to conserve water, and aesthetics. While we're of the opinion that each of these would make a great addition to the majority of family households, it's important to compare them with alternatives before rushing into a decision. We have various guides to help you do this on our menu at the top.