shower pressure question

[graham1]

Hello everyone,
I'm putting in a bathroom in my 2 floor, 2 bed house. I have a gravity fed system and easy access to hot and cold water pipes running under where shower is supposed to be. I want to put in a thermostatic shower but have a concern about the pressure before I buy one.
Looking at the diagram on the box it shows that a minimum of 1m head is required from bottom of tank in loft to shower valve itself. I just about have this.
If the pressure isn't great I'd like to know if I can fit a pump to these 2 supplys. (shower says it's compatible with a pump)
The cold water supply is from tank in loft to airing cupboard (where HW tank sits) then to proposed bathroom where I'll also use it to supply a sink and toilet, then continues down through floor to supply a downstairs bathroom sink, bath and toilet where it terminates.
The hot from the cylinder follows exactly the same route and runs parallel to the CW supply from the airing cupboard supplying upstairs sink, shower then downstairs sink and bath.
If I need to fit a 1 Bar pump can I put it in the airing cupboard or in the proposed new bathroom on the hot and cold supplies?
Would like to avoid extra work of new dedicated CW tank supply and dedicated HW cylinder supply if possible.
If I can will the pump start running if the hot or cold water is used or toilet flushed in either bathroom?

Thanks.

 

[dal5band]

Before fitting a pump you need to check the size of the CW tank in the loft - a pump takes water faster then the tank fills up so just need to check the tank around 40-50 gals (100 litres).

If you decide to use a pump, it's best to plumb it so it just feeds the shower - if you fit a pump for the whole house it will be quite noisy everytime someone opens a tap or flushes the loo and it will wear the pump out quicker with a lot of stop start operation. Go and listen to someone else's pump running - you'll see what I mean.

Then you need to investigate how pumps are connected to the tanks - the correct way is for the pump to be fed directly from the Hot and cold tanks although I have had a pump under the bath which seems to have worked OK for years.

 

[graham1]

Thanks for prompt reply dal5band,
Am fitting the shower tomorrow so will see if pressure is reasonable or not.
The CW tank in the loft is much larger than 100 litres so shouldn't be a problem with pump.
I don't fancy the pump switching on every time the water is used elsewhere in the run so will take your advice and carry out any extra work to fit a dedicated hot and cold feed if required.
Just a few questions regarding the pump if you have time and can help;

Can the pump be fitted at the location of the shower under the floorboards rather than at the HW cylinder? ( it's about 3m away on same floor and would make plumbing less awkward)
Is a 22mm essex flange suitable? (From reading other posts)
Any pump you'd recommend in particular with low noise/ reliability/ value for money?
Thanks.

 

[dal5band]

Sorry I've been away for a couple of weeks so I hope you've done it all by now. In any case I'm just a DIY so couldn't really give any details.