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Community and Q&A

Separate water lines for toilets?

greenleopard | Posted in Green Products and Materials on

I’m getting ready to replumb my house, and thinking of running separate lines for my hose and toilets (not on the water softener or water filters). This would be useful to save on water softener electricity, wear and tear, salt, and water filters. I’ve calculated the payback to be 30 months, given $100 in pex supplies to run a separate line for the toilets, this is not counting any hose usage which would make it even shorter.

An average usage is 50 gallons/day/person
So for 6 people, 300/day, 9000/month
26% is for toilet use (national average)

use 26% less water softener electricity, salt, regeneration
use 26% less water filters
filters are $100 / 70,000 gal, at 9000/mo that is 7.8 months
or $12.8/month, so 26% is $3.30/month
cost to do separate hard water lines $100
payback in months 30

The only downside I can see is the toilet gaskets possibly wouldn’t last as long, but that is unknown if it’s true and the effects. I’ve searched but not seen any info on this, any comments?

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not very familiar with the problems associated with hard water, but I understand that these problems include the accumulation of lime scale. I imagine that lime scale will build up in your toilet tank if you supply the toilet with hard water.

    I'm not qualified to comment on whether such a mineral buildup will cause problems -- but I imagine it might.

    -- Martin Holladay

  2. Dana1 | | #2

    Lime scaling is a very slow process, unless the water is being heated. With a code-legal low volume modern toilet it would probably take decades (if ever) before liming was enough to interfere with the float valve or flapper etc.. Those replacement parts are pretty cheap, but a chemical treatment of the tank to dissolve visibly built up lime to would likely be even cheaper. Any problems are more likely to be cosmetic-only.

  3. seabornman | | #3

    Two things given experience at my house:

    1. If your outside spigot is not conditioned you will get spots all over your car when you wash unless you hand dry the whole thing. I run a hose into basement when I wash car and when I need better water outside.

    2. Do you have iron in your water? Toilets will get brown stains that require occasional treatment.

  4. greenleopard | | #4

    I plan on running a hose bib with soft and filtered water near the driveway.

    I think there is some iron in the water, but I've never had problems cleaning the toilets as it is now with hard water. I'm thinking I'll use a chemical treatment if it's needed.

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