Tedious plumbing/boiler question

[Kemmo]

We currently have a conventional boiler (about 12 years old) with hot water tank in airing cupboard and cold water tank in the loft.
And a fab power shower.

We're currently planning a loft conversion. Do we:

a) Keep current system and just move the cold tank into a corner of the loft.
Advantage of this is that the we know our current system works really well and would mean we could keep our current fab shower.

b) Move to a combi boiler
This give us more loft space. And presumably we will need to replace our boiler reasonably soon anyway. So it seems to make sense to do this at the same time if we ever plan to shift to a combi. But we'll be really pissed off if we end up with a less good shower than we have now.

Or something else?

FWIW we have pretty good water pressure.
And at some point in the next few years will want to fit a new shower in the second (existing) bathroom.

[MILdesperandum]

C) Change to an unvented system with no water tank in loft (hot water at mains pressure). Combis are less preferred where there are multiple bathrooms I believe. This is what we are having put in in the next few weeks ridiculously excited

[Kemmo]

see I knew there'd be third way :)

But how do I know in advance that that will give us good enough water pressure for a great shower.

It is going to involve buckets and a stop watch right?

And am I right that that is the same as the combi approach in that I'd have to get rid of our fab power shower?

[MILdesperandum]

Ha - yes get the buckets out and hope PigletJohn comes along to answer your other questions! no idea whether you can have a pumped shower with the unvented system but from what I've heard you won't need one...

[hamburgerlady]

If you can afford it get a combi' O.P. Vaillant or Worcester Bosch. DP has just fitted one and it's great. Really small, efficient and no need for tank.

[allthatglittersisnotgold]

We had the same issue not so long ago, and spent ages thinking about it because we were having a loft conversion.

We have terrible water pressure, and I mean awful, if someone ran a tap in kitchen shower was a dribble. Also if downstairs neighbours have a shower I belive both of us have a dribble!
This is what we did.
Took out the combi boiler in the kitchen (which freed up space there).
Moved a new boiler, hot water cylinder and "megaflo" into the back portion of the loft space ( we are fortunate enought to have loft space over the entire flat (altho not all head height suitable for conversion).

Now I don't know the technical term for this system, but a pressurised system as oppose to the old fashioned gravity fed systems, means that hot water (normal rads) and good showers can go to our loft conversion. Since having it put in all taps can be blazing and showers are hotel pressure strength.

Basically the "mgaflo" stores the cold water and as it empties when it gets to a certain point it refills. (slightly noisily), was fairly expensive but worth every penny.

[hiccupgirl]

We had the same issue only our back boiler was 30 yrs old so had to be replaced. The power shower that ran off the hot water tank was amazing.

Our plumber was brilliant and really got that this was important to us. We had a combi boiler but with a pressurised shower system that has a separate mixer in the loft before it feeds back to the shower. It was pricy at £600 but it is the best shower I have ever used and even posh hotel showers rarely come close. We have pretty good water pressure though.