Dual Flush toilets (#1s and #2s)

[Nick]

Hi,

I currently have an 'ideal standard' bog standard ... bog. Housemate has some kind of bladder problem meaning he's at the loo 3 times an hour. I'm fed up with the waste of water, and am interested in getting a dual flush cistern, so he can use half flushes for #1s.

Does this mean replacing the whole toilet? Is it possible to change just the flush mechanism, or is this specific to each cistern. Are cistern's standard, or if I change it, will I have to change the bowl too?

Or does anyone know how to modify a standard flush cistern to make it dual flush?

Thanks for any help Nick

[Andrew Gabriel]

I'm not sure if they're still around -- they didn't work (in saving water) because people didn't know they were dual flush, and used the #1 flush for #2's, several times until it worked.

I think current toilets are down to a 6 litre flush now anyway.

The design of the S-bend in the toilet matches the volume of flush. If you put a recent 7ltr or 6ltr cistern on an older bowl, it often won't clear the contents. You could try the classic trick of putting a brick in the cistern, and see if the bowl still works with reduced volume.

Other options are get the bladder sorted (should at least get it investigated to make sure it's not something like untreated diabetes), or fit a urinal.

Another thought which crosses my mind occasionally is to rig something up to flush the toilet from the rainwater butt, if it's got water in it. Never got a round tuit though...

[Chibblegrips]

You can stil get them - the Multiflush from

one that I have used. It`s a push button flush - you push the top half of the button to get a 3l flush. I seem to recall that plumb centre stock them.

Does he / she need to flush every time?

"If it`s yellow, let it mellow --- If it`s brown flush it down"

Will Plummer

[Lobster]

Pretty sure you could just change the innards of the cistern, they are pretty standard; you certainly wouldn't need a new bowl (unless yours is highly non-standard).

How old is your cistern though? Older models (pre-metering) use a hell of a lot more water than modern ones, so might be worth replacing it anyway. If I were you I'd do my sums first though and work out how much your mate's bladder problem is actually costing you, before using that as the basis to start renewing everything. One possibly useful tip - my water co is plugging the use of a 'save-a-flush' device in old-style cisterns, and provides these free to customers; they basically swell up inside the cistern and reduces the flush volume by

1 litre. A house brick or two does a similar job.

See

(or PS Trust your housemate's seen the doc? Shouldn't muck about with a problem like that; waterworks problems in blokes are taken a lot more seriously than in women...

[Dave Liquorice]

Beat me to it...

If housemate needs to visit the loo every 20 mins I suggest he needs to visit his doctor and urgently. It could be a symptom of something really rather serious, diabeties has been mentioned, prostate problems can also have similar effects. These sort of things do not just "go away" they *need* treatment.

Of course he could simply be drinking a full glass of water every 10 mins and needs to get rid of the excess fluid but that's not good for the body either...

[Jethro]

Now I've been wanting to do this for a while. It seems such a good idea (practically zero-cost if designed in from start) and has potential for such environmental saving that I'm amazed it isn't mentioned more often.

I have a little problem though. I live in a bungalow, so filling a tank which would be *higher* than the cistern(s) is a bit tricky due to gravity.

Anyone know of an environmentally friendly way to lift a buttful of water into the loft ... solar power ? It needn't be fast, a trickle would do over

24 hours ......

[Jethro]

Now I've been wanting to do this for a while. It seems such a good idea (practically zero-cost if designed in from start) and has potential for such environmental saving that I'm amazed it isn't mentioned more often.

I have a little problem though. I live in a bungalow, so filling a tank which would be *higher* than the cistern(s) is a bit tricky due to gravity.

Anyone know of an environmentally friendly way to lift a buttful of water into the loft ... solar power ? It needn't be fast, a trickle would do over

24 hours ......

[Owain]

"Jethro" wrote | Anyone know of an environmentally friendly way to lift a buttful | of water into the loft ... solar power ? It needn't be fast, | a trickle would do over 24 hours ......

In a bungalow, an above-ground water store would be at about cistern height anyway. It shouldn't be too difficult to have a dual-action flush such that the pull lifts water from the butt to the cistern and when the chain is let go the weight of the water in the cistern does the flush.

A more advanced version would use the weight of the person sitting on the pan to lift the water into the cistern.

Owain

[Owain]

"Jethro" wrote | Anyone know of an environmentally friendly way to lift a buttful | of water into the loft ... solar power ? It needn't be fast, | a trickle would do over 24 hours ......

In a bungalow, an above-ground water store would be at about cistern height anyway. It shouldn't be too difficult to have a dual-action flush such that the pull lifts water from the butt to the cistern and when the chain is let go the weight of the water in the cistern does the flush.

A more advanced version would use the weight of the person sitting on the pan to lift the water into the cistern.

Owain

[Lurch]

On Mon, 28 Jun 2004 15:52:47 +0000 (UTC), "Jethro" strung together this:

A bucket! Or if that's not to your fancy how about a 12V pump powered from a battery charged by a small solar panel and set on a timer for intervals of whatever works out for the water level\battery charge time. You could always switch to mains power as a backup.

[N. Thornton]

You dont need to get it into the loft.... unless your bog is up there. You need to get it to the bog.

Rapid electronics sell float switches that can be used to turn on a small pump whichs adds water to cistern. Reducing flow of the mains into cistern allows more of the water to come from the garden tank. Be aware that fill flow rate with such setups is frequently a lot lower than expected.

Do filter the water though, dont want it whiffing. Sand makes a cheap and good filter material.

If theres room then a second float ball and valve will enable you to not use leccy.

You can have a separate loft tank to fill the loo, and fill that from the garden, but unless you have a lot of roof collection and are on a water meter it seems an unnecessary expense.

Never put such water into your main cold water header tank!

You might also want a double non return valve on the mains cistern fill. Suggest checking what water regs apply in case not everything is covered here.

Regards, NT

[Nick]

Thanks everyone.

I`m going to go for the multiflush system - it seems the best option over an expensive new cistern, or offending my unimposing, weak bladdered housemate (/lodger).

(any ideas on how to rig up a system where everytime the toilet flushes, our doctor`s number subliminally flashes up in the pan for a split second?)

I appreciate all your replies Cheers Nick

[Owain]

"Nick" wrote | (any ideas on how to rig up a system where everytime the toilet | flushes, our doctor`s number subliminally flashes up in the pan for a | split second?)

A small water turbine in the flush pipe. If lodger is that weak bladdered it might be worth linking to the national grid.

Owain

[Jethro]

good idea

Don't understand this , sorry

we do !

we are

Unless we're odd, we don't have a header tank (combi boiler and all that). Although I take the point. Must not contaminate mains supply.

Didn't think of that ...

Thanks

[Jethro]

Hmmm, make filling the tank part of my fitness regime !!!!! I guess it's the most green option ....

Anyone know of a decent footpump ?

[Martin Brook]

Seems ironic given that the water comes from way above the loft anyway! All that wasted potential energy!

Maybe someone should design a house where the gutters feed straight into to a water tank higher than the cistern?

[N. Thornton]

A 2nd float and fill valve in the loo cistern could be plumbed to the rainwater supply. If theres room in the cistern for it. Now you have 2 supplies filling the thing.

In which case it may be worth having a proper system that uses as much rainwater as poss, complete with sand filter and any other water treatment needed. Ie either:

a tank high up filled with rain, which fills just enough for a flush with mains water when its almost empty.

or a loo cistern with float switch plus rainwater tank with water level detector, and a simple controller that decides which to fill with.

You can also use grey water for flushing. The detergent content keeps the bowl cleaner apparently. I'd want to sand filter it myself. So you could knock your bill on the head almost.

Regards, NT

[N. Thornton]

Its been done but the tanks require filters and ventilation to outside, and the loft floor has to be a lot heavier to hold the tanks weight of 1 tonne per m3.

Its therefore more attractive to have tanks at ground level and pump.

Regards, NT

[Jethro]

Yet again, it seems crazy that something that is relatively simple and straightforward doesn't happen because of inertia .... I'd guess 80% of household water is used for loo-flushing. Since being metered, we fitted one dual-flush loo (the main one) and had a dramatic decrease in water consumption.

I wonder what percentage of the billions of squid the water companies will spend on fixing leaks and upgrading could have gone towards funding water-reclaim projects which would have reduced the demand ....

[Chris Doran]

But in the OP's case, it's a bungalow, so the tank could be outside on stilts -- one metre should be enough, and useful storage space underneath.

From my own experiments using the bucket method, though, you need to store an enormous amount of water to cover dry spells, when you'll be using it on the garden too. I never had any whiff problem with unfiltered rainwater. I also use grey water, but it doesn't keep the bowl any cleaner -- limescale still builds up just as fast in this very hard area. From my school chemistry, ISTR that detergent in fact precipitates it.

Chris