Bathroom colds - gravity fed to mains pressure?

[foggy]

Sorting out a bathroom refit at the mo and have had a bit of a plumbing brain fart for which I'd be grateful for the knowledge and advice of those in the know please...

Currently my bathroom recieves the feed for toilet and sink and bath cold taps from a tank in the loft so gravity fed, and sink and bath hot as DHW from a combi boiler so mains pressure. There's also an electric shower, which I'm 99% sure receives mains pressure cold tee'd off the loft water tank supply which comes down through the ceiling and is clipped on the tiles before entering the unit, a classy bodge by the previous owner! The water tank supplies the bathroom colds only and nowt else and it's only a 3 bed semi so I'm not going to want any gravity fed water elsewhere in the future.

I'm thinking, it wouldn't be a difficult job to take the loft tank out of the system and connect the cold main directly to the bathroom cold supply as the pipes run within inches of one another up to the loft space and then back down again to the bathroom. Is it worth doing, and what are the pros and cons?

Basically I can see I'd lose the ability to store some water in the tank (potentially gaining some loft space for a little extra storage after removing the tank) and would have hot and cold feeds at similar pressures at the taps.

And I plan on installing a mixer shower, so presume it will need a cold supply at mains pressure to match the DHW? This could be done by piping from the hot tap up to the shower in the wall, and then tidying up the tee'd mains pressure cold supply running down to the current shower, also putting it in the wall. If I take the tank out the system and have mains pressure hot and cold bath taps, I can continue these both to the shower.

Answers on a post card please. Don't be afraid to hold back with straight answers to a plumbing div - I can solder joins with aplomb, now I need the theory!

Ta.

[redeye]

yes in loft conversions we do it all the time , no probs ,no gains,yes space in loft ,cost why do it
you will have to change flow valves in the toilet to mains feed ,thats it

[fatboy b]

redeye said:

yes in loft conversions we do it all the time , no probs ,no gains,yes space in loft ,cost why do it
you will have to change flow valves in the toilet to mains feed ,thats it

Not necessarily. We converted all our cold to mains when we did our main bathroom & en suite out. The downstairs loo valve wasn't changed, and was fine with mains.

[98elise]

Ideally keep the toilet on the tank, nice to have some stored water for flushing if every you get cut off.

That said its only ever happened to me once in 20 years!

[Ferg]

98elise said:

Ideally keep the toilet on the tank, nice to have some stored water for flushing if every you get cut off.

And it cuts down condensation on the cistern.

[foggy]

Ferg said:

98elise said:

Ideally keep the toilet on the tank, nice to have some stored water for flushing if every you get cut off.

And it cuts down condensation on the cistern.

Presumably because water from the loft tank is generally warmer throughout the year than that from the main so warmer cistern = less condensation forms on the surface?

So, I'll tee off the cold main to feed the sink and bath taps and shower. What's the verdict on Aqualisa mixer showers? Any other brands recommended?

[Simpo Two]

Ferg said:

And it cuts down condensation on the cistern.

Interesting point - I left a friend's toilet and had to say 'By the way that puddle all over the back of the pan wasn't me!'

Edited by Simpo Two on Saturday 15th January 11:24

[Ricky_M]

Remember to remove any gate valves from the pipe work, they are not designed to be used with high pressure water.