low pressure after stopcock switch off

[BVP]

I had to switch of the mains water and after switch on got low pressure. After the basic checks of running water through all the taps and all apliances no improvement. so I guess the fault is the stop cock and need replacing and there is there is the problem. The house was built in 1971 and the stopcock outlet is half inch copper, that shouldn't be a problem the inlet is probably mpde but I fear that is imperial so any suggestions of what size of stop cock I should be looking for would be welcome

Bernard

 

[ianmcd]

If it is MDPE it is metric, if it is black PE it will probably be imperial.

https://cityirrigation.co.uk/acatalog/pipesize.html

 

[BVP]

Thanks for the catalogue the sizes will help me. Will get my calipers out and measure it. Quick response appreciated.