A few plumbing questions.

Avoriaz

As in the picture left above, under the kitchen sink I have a rising main with a stopc0ck followed by a Pressure Reducing (Limiting) Valve set at about 2 bar. This then feeds all the house plumbing including the garden tap. Everything is mains fed. There is no cold water storage tank in the loft. There is a stored hot water tank integrated with the Potterton boiler on the first floor so I don’t have a combination boiler. At present I get a very decent flow in the shower and at all taps.

I am installing a water softener (Kinetico 2020c High Flow model) so I need to make some plumbing changes. I want to maintain flow rates, especially in the shower.

I want to have a hard water feed to a second garden tap (giving me soft and hard water options for outside) and to a drinking water filter so obviously these need to be fed from before the water softener.

Can I also feed them from before the PRV so that I get maximum pressure and flow in the garden and at the drinking water tap?

I assume that the PRV should be on the supply side before the softener.

Should I increase the setting on the PRV to 3 bar to compensate for the inevitable slightly reduced flow through the softener and maintain a decent flow in my shower? This assumes that the supply is at least 3 bar.

At present the stopc0ck is positioned just above the floor of the undersink cupboard. Can I lower it so that it is below the base of the cupboard or will being very close to floor level cause problems? It will be easily accessible behind the kickboard. I realise that means closing off the water board supply in the street to do the work.

I plan to install things in this order as indicated in my rough picture on the right above.

Rising main: Add elbow so that it runs under cupboard floor
Stopcock: Now horizontal under cupboard floor
Tee off with service valve for hard water: Under cupboard floor
Elbow to above cupboard floor on right of cupboard to leave room for softener on left.
PRV
Supply valve to softener (normally open)
Softener Bypass valve (normally closed)
Flow valve from softener to house (normally open)


That seems logical to me.

Am I missing something?

Thanks