Dual Flush Toilet

August 3, 2009 6:54 PM

The latest issue of Good made me feel like I use water wastefully. Is it more cost/eco-effective to retrofit my existing toilets with a dual-flush kit, or should I go for a latest-gen low-flow dual flush toilet.

All of the toilets in my house are first-generation (post EPA mandate) 1.6 GPF toilets, which work with varying success. The upstairs toilets, either due to design or a quirk in water pressure, rarely clog, while the downstairs toilet will often have issues with solid waste. These are issues we've dealt with for years, and I've replaced flappers and pumps as needed.

A quick Google search shows me that there are some kits available for retrofitting toilets to have a dual-flush option, but some looked a bit sketchy. Has anyone here tried one of them and had success?

If those are more trouble than they're worth, or too expensive considering my family may replace the toilets before we move out (probably will happen in about 2 years), what are some good latest-gen low flow dual-flush toilets? Is it easy enough for a novice to install a toilet, or should I hire a plumber?

posted by mccarty.tim to home & garden (10 comments total)

IANAP, but if the flow in the upstairs loo is decent, you could simply stick a brick in the cistern as has been employed as a water conservation method since days immemorial.
posted by pompomtom at 6:56 PM on August 3

There are a lot of sources that say not to put a brick in the toilet tank, because it may disintegrate over time and its little bits will harm your plumbing. Search "brick in toilet tank" on your favorite search engine. A plastic jug with sand and water is a better option.
posted by mistersix at 7:13 PM on August 3 [1 favorite]

Re: Brick: The upstairs toilets seem to work just well enough that I'm worried they couldn't handle solids if I reduced their output any more. What I'm hoping for is an intuitive solution for smaller flushes for liquid, preferably a dual-flush system rather than something like an adjustable flapper (it'd be confusing for guests and inconvenient).
posted by mccarty.tim at 7:31 PM on August 3

Do you have low flow shower heads on your showers? Many of the studies I have read say that the dual flush toilets do not save nearly as much water as low flow shower heads.
posted by markblasco at 9:40 PM on August 3

Where do you live?

It it's in the Southwestern US then water conservation is a very big deal, if you live in the Northeast then not so much. From an environmental view, fresh water (unlike carbon dioxide emissions) is not fungible - that is, it does matter where you are located, because the impact is strictly local.

Depending on where you live, you may benefit the environment more by spending the money on energy saving - or reducing how many Californian vegetables you eat.
posted by atrazine at 9:41 PM on August 3 [1 favorite]

It's my opinion that no matter where you live, conservation is important - it's got to come from somewhere to get somewhere.

If you don't have guests often, but do have family toilets that wouldn't confuse or be used by guests, you might consider approaching the problem from the other direction - instead of flushing water away, add more.

Something I saw online - a sink built into the toilet tank lid. You could leave a pot there, smallish in nature, but enough to flush pee away if you prefer not to be a "mellow yellow" household.

Need to flush a little? Pour the contents of the pot into the bowl, and the toilet will perform a small flushing action. I don't know how much - possibly four cups, or even six? But do it in one motion. It's how we "flush" when the power is out and we're using grey water from the capture tank or tub for flushing necessity.

And previewing above, I agree on the other methods for home water conservation - low flow shower heads, capturing shower water for garden use (using enviro-safe cleaning agents!), rain water barrels, shaving and teeth brushing with a cup or two of water rather than a running tap (I'd not share shaving water and teeth brushing water unless you're worried about plaque on your chin).
posted by tilde at 9:56 PM on August 3

Low-flow and dual-flush toilets suck, unless they're pressurized (and those are troublesome because they break all the time). I have a brand new dual-flush toilet in my new eco-friendly apartment, and sometimes I have to flush the darned thing two or three times. And don't even get me started on the low-flow faucets.

If you really want to save water, stop eating meat! The production of animal-based foods is responsible for 50% of the fresh water use in the U.S., and is rapidly draining the fossil aquifers of the Southwest. Those aquifers do not refill, at least not on timescales relevant to human civilization. They will run out, and then there will be no more water there!

Having veggies instead of steak just once will save more water than retrofitting your toilet or even skipping your shower every day for a year.

(Source: The Food Revolution, John Robbins, 2001)
posted by brain at 1:26 AM on August 4

It's a difficult call, but if I were in your shoes, I'd replace any toilets that have difficulty flushing. They're not working properly anyway, so why not get something new that's water-efficient as well?

But a dual-flush toilet isn't the only way to save water: low-flow showerheads, aerators on taps, and all sorts of stuff in the garden can also make serious cuts without you having to form new habits (which is always the part that ends my efforts). Save water in the home has some more ideas.
posted by harriet vane at 4:36 AM on August 4

@brain: dual flush not working?
Really? I've a dual flush I installed a couple of years ago in our only bathroom for a family of three. It's dealt with everything we've... thrown at it... easily and efficiently with a single appropriately selected flush.

I've read not all toilets are created equal in the dual and low use arena. Read reviews / reports on their performance before selecting one. I believe low-flow toilet bowls were designed to allow for using less water per flush - I can't imagine a conversion kit working all that well on a bowl expecting more water.

I was fearful of doing the replacement myself, but read a number of 'howto' instructions online and decided to give it a try. It took this non-handy person about 20 minutes. The hardest part was lifting the old, heavy bowl.
posted by csmason at 6:37 AM on August 4

In case you haven't seen it: Terry Love's toilet reviews. The forums are also useful.
posted by The corpse in the library at 7:29 AM on August 4