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Low-flow Toilets: How (Not) To Install One

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Winston Churchill (who had an American mother) is supposed to have once quipped in a moment of wartime frustration with his best allies that:

"Americans can always be counted on to do the right thing...after they have exhausted all other possibilities."

I'm a bit like that as a handyman. The job gets done, usually without serious injury or loss of expensive parts, and gets done fairly well. But it rarely seems to be as smooth, efficient, or rapid as it could possibly be. But perhaps my bumblings can save you a bit of time. Let's see--if, that is, you want or need to replace an older, inefficient toilet.

Upgrading to low-flow toilets is a popular DIY project these days, and for good reason. If you have older toilets, you are probably using from three and a half to six gallons per flush. (Mine used about 4.5 gpf.) A modern low-flow model uses 1.28 gpf. For simplicity, let's say that the saving is 3 gpf. Obviously, the water used will be the gallons per flush times the number of flushes times per day. So, if there are ten flushes per day, 30 gallons will be saved daily--and 900 gallons monthly, or 9,195 gallons a year.

For some of us, those numbers will produce dollar savings worth mentioning. Some--especially those of us who live in areas whose water supply is stressed or at risk--may just wish to do our bit to help conserve a valuable resource. And for those concerned about carbon footprint, all that water is pumped electrically--and the biggest proportion of US electricity, nearly half of the total, is generated by the most carbon intensive method--burning coal. (You can read more about that at this link.)

And there's another motivation, too. Like any other device, toilets wear out. This is a great time to replace them, as many areas are offering subsidies to go to low flow units. In our case, we picked high efficiency units priced at $106. They are eligible for $100 rebates. (Enough said.)

So, what's the project like? Not too bad. Let's go step-by-step.

Image courtesy McGill & Wikipedia Commons.

Image courtesy McGill & Wikipedia Commons.

That old toilet's got to go. . . OK, that was bad.

The first step is removing the old toilet. As shown in the image above, most toilets are 2-piece affairs, with separate tank and bowl. So you have a choice of removing the pieces separately or as a unit. Most people prefer to remove the pieces separately for ease of handling. However, situations are different, and a shelf unit above and behind our toilet restricts access to the inside of the tank. Since that's where the bolts holding tank and bowl together are, it made more sense in my situation to remove both as a unit--which means no pictures of this part of the process!

Luckily, it's not hard to figure out how to remove the tank. First, turn off the water! (There's virtually always a valve controlling the water supply to the toilet. You can see a photo of this below.) Then flush the toilet to empty as much water as possible. You can bail out, or soak up, the rest of the water in the tank if you like, or simply put a container under the first bolt you remove from the tank--realizing that you'll have some mopping of the floor to do.

Once the bolts are removed, disconnect the water line. The tank can then simply be lifted off the bowl and set aside.

Old base, bolt with decorative cap


Removing the bowl

Removing the bowl--with or without tank attached--starts with removing the decorative caps covering the bolts at the sides of the bowl's base.  The photo above shows the bolt, with the cap next to it.  The covers differ, but usually it's just a matter of pulling or prying it up.  Perhaps some may unscrew, though I haven't encountered any that do.

If you're lucky the nut will look more or less like the one above--it's a bit corroded, but not so much so as to be frozen to the bolt--and not like the one below.

Old bolt


Bad bolt options--and how not to illustrate a Hubpage

This is a closeup of the other bolt.  The glop on the right is wax from the tank seal, but the salient fact is that the nut is corroded right onto the bolt.  It just isn't going to come off.

(By the way, you'd be able to see this much better had I not chosen to document this project using my cellphone camera.  Clearly, a second-best choice--or maybe not even that good.  Lesson learned.  And sorry about that.)

You have several options for removing the bolts in situations like this, as shown in the next several photos.

Tool of choice for removing old bolts


But we've already established that that didn't work in my case. In fact, the shoulders of the nut were so corroded that the socket couldn't grip them.  So. . .

Scroll to Continue

Next best tool for removing old bolts


Sometimes a large pair of slip-joint pliers, such as these, can firmly grip what the wrench cannot. But that didn't work either, since the nut and bolt were firmly "at one." And there really wasn't enough space to try to hold the bolt end still with a second set of pliers. So, could I cut the bolt. . .?

Maybe a Jigsaw can cut that old bolt


Not with a jigsaw. . . the base meant that I couldn't get the blade onto the bolt.

Or perhaps the Hacksaw can reach it better


The hacksaw could at least reach the bolt, but I wasn't sure that there was enough clearance to cut all the way through.  I didn't want to damage the finish on the porcelain.  And the nut really got in the way, making progress glacially slow.  So. . .

Tool of last resort (but it's guaranteed to work)


Remember, the title of this page starts, "How (not)".  I'm not recommending use of a hammer, OK?  Broken porcelain has some really, seriously sharp edges, and a person could cut themselves very seriously.  (A broken casserole lid once got me for a trip to the ER and several stitches.)

It's just what I chose to do.  And I was awfully careful cleaning up those sharp bits of porcelain, as well as handling the old toilet--understandably, I suppose, given that casserole lid episode lurking in the back of my mind.

Clean up tool of choice


A vacuum is about the only thing that will get all the small shards. It also keeps them far away from your fingers during the cleaning process, which is a very good thing. Of course, I started by sweeping up the larger pieces . . . carefully.

At this point, I needed a break. Having made one questionable choice, it's important not to have the consequences of that choice create a cascade of further bad choices. So I took a few minutes to clear my head, let the frustration disperse, and just think about the project in an unpressured sort of a way.

All this is to say that managing one's mood is important during any DIY project. Calm is the most important tool we have.

An especially powerful tool


Looking back, I'm wondering about this choice, too.

Here's a before-and-after set of the area. It's worth mentioning that the "before" set isn't nearly as nasty as it might appear to be. The smudges are a compound of rust, ordinary dirt, and that sticky wax from the seal that I mentioned. No need to feel squeamish!

Note that the flange is plastic, and sits above the tiles. Older flanges are metal, which has the unfortunate habit of corroding. And when the tile is laid over the original floor, the flange is very apt to be below tile level.   (Both were true of the other installation I did in our house.)  More about that later.

Flange with new hardware


Nice new shiny bolts!  One is in place already.  The instructions for our new unit didn't make clear where the plastic washers were supposed to go, but it seemed logical to me that they should go between the metal nut and the porcelain of the base of the bowl.

We chose the Glacier Bay High Efficiency Toilet, a Home Depot house brand. It's very economical and has received some decent reviews. It works great so far--we'll see how it holds up over time.

These photos show the box on a furniture dolly I used, followed by the contents unpacked. The dolly is a great convenience--even a necessity for some--as the stated gross weight of the box is 95 pounds. Alternately, you could partially unpack the unit to split up the weight. (One reviewer mentioned that he did just that in the store parking lot!)

Original and Extra Thick Seals


The photo I hate the worst in this Page! But I thought it was important to show seal options. On the left is the supplied seal; on the right, an extra-thick seal you can buy separately. If you have one of those below-floor level flanges, you're going to need the thick one. If above floor level, just use the supplied seal.

The annoying thing is that unless you've removed the old toilet before going to the store, you don't know which you're going to need. (The extra-thick seal went back to the store, in this case.)

New bowl installed


Mounting the bowl is fairly straightforward, and in the case of our unit, the supplied instructions were quite good. They suggest placing the seal on the inverted bowl, twisting and pushing gently to adhere the wax to the porcelain, and then lowering seal and bowl together onto the flange. (I had a picture of this, but it's absolutely unusable.)

I had to line up one bolt, set an edge of the bowl down, and use one hand to guide the remaining bolt through the other hole. Then simply apply plastic washer, metal washer, then the bolt. Follow that up with the decorative cap, according to the directions supplied.

Remember that you really, really don't want to overtighten the metal bolt. The following picures, I think, make clear what can happen if you do.

One other trap should be mentioned here. The instructions specifically told me to make sure that the flange bolts were the correct length before doing the installation of the bowl--otherwise the caps won't go on.

I forgot all about that part, since I hadn't had a problem with bolt length on the first toilet I'd done. Bad idea--while the first one had had a low flange, the one here had a high flange, making the bolts way too long. I had to cut them, either in place or after removing the bowl again.

I went with cutting in place, mostly because I was afraid of mangling the seal too badly to reuse. That put me right back with the hacksaw, though it worked better with the new bolt than the old. But I did put small scratches on the finish, and incur a minor ding on one knuckle.

I blame the beer.

Bloody knuckle


Oh, well. Onto the tank installation. Below are two photos; one shows the hardware, resting on the bottom of the inverted tank; the other shows the tank interior, with the lever installed. (I chose to install the lever before mounting the tank, because of that shelf unit obstructing tank access. Usually it's better to do it the other way.)

This was one instance where the instructions were not so good. A good bit of the hardware you see is apparently superfluous. Perhaps some--and here I'm thinking mostly of the plastic bit on the connection for the water inlet line--is meant to protect parts during shipping.

I chose not to try to use the oblong metal washers and the wing nuts you can see. They are flimsy anyway, and not found on the other installations I've dealt with. So far, nothing bad has come of that choice.

I also wondered a little bit about the logic of pulling that foam gasket over the threaded tank outlet.  Why thread something, then cover up the threads?  But the instructions were clear on that point, at least--and the old toilet had a similar arrangement.

Yep, they sure do.  Here are photos--the good one is of the old line, still in place on the 1/4-inch line from the wall.  The crumby one of its replacement, a 12-inch PVC line.  I needed a replacement because the new toilet is a 17-inch high model--these are increasingly common, as being arguably more comfortable to use, and more friendly for aging knees--and the line was meant for the old standard of 15 inches.

Still, it really looked like it was going to be long enough anyhow.  Another trip to the store, darn it.

Attaching tank to bowl


In case you're wondering, the photo above shows the tank mounted on the bowl and tightened down. The point is that the tank is even and level--and the bolts are not over-tightened. You want to go slowly and carefully while tightening down the tank bolts. (If you're unsure about the importance of this point, scroll back up and contemplate the "old toilet" photos again.) You do want the attachment to be firm, of course--but no more than that.

Water On!


With the tank attached, and water line connected, you can turn the water on.  It's a good idea to check for leaks, particularly at the water line.

Somewhat uncharacteristically, I didn't find any.

If you don't either, enjoy the moment, then proceed to check the water level in the tank--our instructions had procedures for adjusting this, but everything was fine as it was--and attach and connect the lever, if you haven't done so earlier.

The only thing left to assemble is the seat.

Installing the seat


The instructions were a little vague again at this stage, but then it's pretty self-evident what needs to happen.  In the case of our unit, the rubber--should I call them washers?--clearly had to go where the photo shows them.

Seat installation is apt to differ widely from brand to brand.  For that matter, upgrading seats is pretty common--you can buy various replacements at a whole variety of price points, if you wish.

All done!



It took about four hours, including modifications to that shelving unit I've mentioned, and two trips to the store. An ace could have done it in two, I'm sure, and maybe in close to one. But in case you hadn't already realized it, I'm no ace. But the price was right, and I got to share the experience with you, bumbles and all.

Perhaps I could have saved a couple of bumbles had I found this site before I did the installation:

Try it and let me know!


After 6 months of use, these units have performed well. Oh, there have been a instances--probably fewer than half a dozen--requiring a second flush. And once I had to reconnect the chain connecting the flush lever to the valve. Cheap hardware!--but probably fixed for good with a simple squeeze of the pliers. We're still very satisfied!

Second Update

The units discussed are still doing OK in 2014, five years after initial installation. There were some further issues with the chain/flush lever, and the seats are still cheap and annoyingly needful of periodic tightening. But overall, we're still quite happy with these units; witness the installation of a third Glacier Bay toilet in our lake house!

That unit is even stingier with water, using just 1.0 gallon per flush. It works great, and installed much as the previous two. The instructions are still poor, and there were superfluous parts included with the kit once again. The seat is better quality, though, noticeably more solid. Who knows? Maybe it won't need tightening quite so often.

Either way, this Glacier Bay unit performs well, saves water, and costs comparatively little.