Advice - remove water tanks in loft, replace showers and boiler?

[spacedmonkeys]

Current setup:
Cold water tank, and header tank in loft.
Hot water tank in airing cupboard at top of stairs.
Power shower (mira event xs) in main bathroom, and same in en-suite.
20 year old Baxi boiler, still going strong.

Background:
Need to free up as much space in loft for conversion. Enough room for two bedrooms but would like extra space on landing for a desk. Removing water tanks will allow this.

Thoughts (I am in no way a plumber or electrical trained - I work in IT):
Replacing current boiler with a combi boiler will remove the need for tanks in loft and the hot water tank?
However my understanding this means replacing both of the showers as they have built in pumps?

Just looking for some general opinions on what would be the most cost effective way to go.
Obviously don't want to create tons of extra costs by needing major bathroom work, retiling etc.
Any alternatives to the above?
Would the Mira's be able to be straight swapped for electric showers?
If the cold water tank currently supplies toilets, hot water tank, and upstairs taps, is there a massive load of plumbing required to supply these from elsewhere?
Many thanks in advance.

 

[ShaunCorbs]

Combis arnt recommended for more than one shower as they can’t cope with multi demands at once

Best to have an unvented you can get horizontal cylinders so they can be in the eves etc

 

[Ben-gee]

Turn the showers off electrically then the pump won’t run.

 

[king of pipes]

Your creating more living space this no doubt will require a further bathroom or ensuite ? , it's time for a full upgrade combi boilers are not really suitable for more than one bathroom, I would be advising the removal of everything and replacing with a new boiler and unvented cylinder , this will mean changing the showers aswell in my opinion it's not gonna be cheap either and with all the build costs for the loft beware as costs can run away and eat into your planned budget, regards kop

 

[Timmy D]

Test flow rate/pressure of your mains. If it’s crap, an unvented won’t be any better than a combi.