use a burco cup once youve done what the apprentice told you, you should be looking for a flow of 15 litres plus, anything less consider going on a seperate supply, otherwise your flow will seriously be affected by the guy or girl downstairs.
If you live in manchester or london i can do this...
I seriously disagree
The standard legal pressure is 9 litres per min at a working pressure of 10 m/h (1 bar).
If you go of the guideline of running 20 litres per min your pressure unless you have a brand new 25 mm PE pipe would drop to virtually zero
Do all taps seem to be the same...