Replacing old designs of taps with new

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Hi. I have an old house with a number of old taps I am hoping to replace with newer designs. None of the taps currently have flexi tails or isolation valves, but I can turn the water off upstream. I haven't changed a tap before (though have done some plumbing), so for each I am looking for advice please on how much of the existing plumbing/sink will need changing too, and what tools will be needed, as I know some specialist tools can be needed with taps.

Kitchen sink
Hopefully this is the most straightforward of the three. I am looking to replace this:
355945192_3182173292082706_5411232120594210444_n.jpg

For one of these:
1687619600517.png

The plumbing underneath:
Kitchen mixer plumbing 2.jpg


While it looks like the hole in the sink should be fine to accommodate the new mixer, I am not sure about the plumbing. For one, the pipe seems to taper (into 15mm?) This isn't something I've seen before. Then the spiral clamp thing. To free the mixer tap, would it just be a case of undoing the nuts on both pipes and the bolt, then the clamp should come off? Which tools are best in this space? Then for fitting the new pipe, would I need isolation valves and flexi tails? Or flexi tails with built-in isolation valves? If so, there isn't a lot of pipe I can cut before it tapers (as presumably I can't cut it past the taper?) Won't be able to get the pipe slice in here too - so is one of these best in the space?
1687620415152.png


Bath shower mixer
I currently have one of these.
1687620503449.jpeg

It's a real pain having separate controls for hot and cold, so am looking to swap for this:
1687620567520.png

The plumbing:
1687620610646.png

So this one only goes through the bath in two places (no bolt in addition to the two pipe connections?) And again, no flexis or isolation valves. Similar questions here please - how to get the tap out (is it just those two nuts on each connection, and if so which tool - especially considering the one on the far side of the bath won't have great access as I'd rather work from the cold-tap side of the bath than get under it as it's a real mess down there). And then what to do re putting in flexis/isolations. Here there is a constraint of the pipe teeing off quite quickly, so can't cut very far down.

Bathroom sink
This one might be the most difficult. Current separate hot and cold (they were traditional turning taps until I recently fitted a quarter-turn reviver kit, but now they make a loud whooshing noise, I guess because they aren't designed for ceramic glands):
1687620932109.png

The separate taps are annoying when the primary use is hand-washing, so I would like to fit a mixer like
1687621063301.png

I know this will look a bit funny given the positions of the holes and I'll have to plug one up, but I don't think it will look too bad.
More concerning is the size of the holes - would one hole be likely to accommodate the new tap? If not, how straightforward is it to increase the hole size? Would rather not get a new sink. Current plumbing (same for both taps):
1687621314092.png

Access is a lot easier for this one, and there are also no constraints on the pipe length - so if the hole is big enough and I'm happy enough with the odd placement, best would be to cut the pipe as far down as needed and put in flexis?

If you made it this far, thanks, and I'd appreciate any advice whatsoever!
 
Get some monobloc spanners for the kitchen sink tap and basin mixer tap. You seem surprised there’s no flexi hoses, which will mean it’s likely been done proper with copper. Also a junior hacksaw might be better than any pipe cutting tool, just make sure you de-burr the pipe. Tap holes should be ok for the mixer, but will probably look daft.
 
If not, how straightforward is it to increase the hole size? Would rather not get a new sink. Current plumbing (same for both taps):

I increased the hole size on our bathroom washbasin, to accommodate a mixer, in place of separate taps. It was a bit of a risk, but I used a masonry drill bit, and a tiny chisel to chip it away..
 
We plumbers spend a fortune on tools that allow us to access these sort of locations and fittings, in order to get jobs done as timely as we can.

Do you want to make that sort of investment for a one off job?

Obviously you have the luxury of taking as long as you need to DIY.

But... You'd be without services to your hot and cold water, during this period.

If you want to proceed, I would be getting isolator valves for each situation. I don't like ballofixes but use them when I have to.

Isolate supplies cut into pipework as low down as you can and fit isolators.
Then you can work on the hard bit of getting the old taps out and new ones in, at your leisure... At worst, you'll have only one facility out of action, overnight (or three ;))

Oh, and maybe you want to stretch to one of these...

 
OK, if you have an open vent hot and cold supply (gravity) then that's why you have individual outlets and a dual flow mixer tap, they are designed to maximise the flow from the H&C system that you have without the cold mains causing probelms.

If you decide to change to modern ceramic cartridges and mixer taps with their restricted flexi pipes/narrow waterways and cartridges designed for mains hot and cold water supplies then you may be disappointed with the output they deliver compared to what you have just now. Don't get me wrong, you may be lucky and get away with it but more often than not there are issues when making these kinds of changes

The biggest problems I come across when someone does a swap to modern taps on a traditional gravity system is the disappointing performance or taps where either the hot or the cold doesn't work properly and the system has to be redesigned or the taps changed with ones to suit the system.

Food for thought :unsure:
 
As a diyer, you will never remove the bath taps without a fight.

Also forget fitting a mixer tap in your basin, unles you replace the basin for a single tap hole.

Advice, let a plumber fit the taps for you and replace the basin, make sure the taps you buy are suitable for low pressure.

Andy
 
OK, if you have an open vent hot and cold supply (gravity) then that's why you have individual outlets and a dual flow mixer tap, they are designed to maximise the flow from the H&C system that you have without the cold mains causing probelms.

If you decide to change to modern ceramic cartridges and mixer taps with their restricted flexi pipes/narrow waterways and cartridges designed for mains hot and cold water supplies then you may be disappointed with the output they deliver compared to what you have just now. Don't get me wrong, you may be lucky and get away with it but more often than not there are issues when making these kinds of changes

The biggest problems I come across when someone does a swap to modern taps on a traditional gravity system is the disappointing performance or taps where either the hot or the cold doesn't work properly and the system has to be redesigned or the taps changed with ones to suit the system.

Food for thought :unsure:
Ah thanks, that's something I never considered. I just double-checked, and (hot water is tank-fed for all three):

Bath shower mixer: cold is tank-fed
Bathroom basin and kitchen mixer: cold is mains-fed.

I am not sure how to check whether a new tap is suitable for this setup, to avoid back-flow/low pressure/noisy taps etc. I was looking at swapping:

1687857614851.png
for something like https://www.victorianplumbing.co.uk...6cc351-7f95-474e-b1c3-355dd3ac2d0d-2CAF:en-GB


1687857694990.png
for https://www.toolstation.com/deva-snowdon-mono-mixer-kitchen-tap/p25413

1687857726572.png
for something like https://www.toolstation.com/deva-swoop-taps/p97513

But, while the product descriptions mention acceptable pressure ranges (though I don't know what pressures I have available), there's no mention of differences in pressure between hot and cold inputs, and whether the tap is single or dual flow (not that I would know which to choose in each case anyway). Can anyone shed some light please
 
i have a gravity fed hot water in a bungalow and made sure when the bathroom was stripped we ensured 22mm from the hot water tank to the hotwater bath tap - it had 15mm in part of it
I also made sure the taps where suitable for low pressure - the old washer type of taps and the hose i used was an11mm from screwfix
sort of works OK ish , i'm fine with it- not great , but the alternative was to have a pump and that meant a new hot and cold water tank and all the associated changed , and cost was £1000's to do , loads of issues on the loft to get a suitable sized tank into for a pump
I knew we may have issues as the kitchen tap had been replaced with a 1/4 turn cartridge and the flow in that was about 1/2 ......
 
But, while the product descriptions mention acceptable pressure ranges (though I don't know what pressures I have available), there's no mention of differences in pressure between hot and cold inputs, and whether the tap is single or dual flow (not that I would know which to choose in each case anyway). Can anyone shed some light please

The words you need to be looking for are 'suitable for low pressure'.
 
The words you need to be looking for are 'suitable for low pressure'.
Thanks. The shower tap I linked to says "Minimum operating pressure of 1 bar for best performance " - do you know what a conservative lower bound is for the pressure my system likely has?
 
house or bungalow - where are the taps / showers - 1st floor ground floor

I would not expect 1 bar - which i think is a 10meters head

approx measure from top of shower head/taps etc to bottom of tank

1 would not get a 1 bar min tap for gravity feed - but just a diyer
 
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OK , the taps you have linked to, if it was me making the determination, unfortunately are unsuitable.

If you are on a 2 level house with standard height ceilings (~2m) with the cold cistern (CWSC) in the attic ~ 1>2m above the level of the bath taps then you have ~ 0.1>0.2bar pressure in the bathroom with ~ 0.4bar in the kitchen.

The bath mixer tap linked to has a ceramic cartridge and will perform poorly with gravity Hot water judging by the quoted figures
The Sink mixer isn't a dual flow tap therefore there could be issues with the mains cold interfering with the HW supply, that and the min flow figure would suggest poor performance
The basin mixer tap, as was suggested by @HERTS P&D, isn't suitable for the basin you have. You would usually have to change the basin to suit a monobloc tap, that being said, again the choice is a ceramic cartridge type tap that will struggle with a gravity supply.

I would also be surprised if the basin cold was mains fed as usually in these cases all the bathroom water would be supplied from the attic cistern rather than a mains supply run to the bathroom just to supply the basin.

If you search for dual flow mixer taps you will see what is available.
 
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